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Immune_system

The Stanford Question Answering Dataset

The immune system is a system of many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue. In many species, the immune system can be classified into subsystems, such as the innate immune system versus the adaptive immune system, or humoral immunity versus cell-mediated immunity. In humans, the blood–brain barrier, blood–cerebrospinal fluid barrier, and similar fluid–brain barriers separate the peripheral immune system from the neuroimmune system which protects the brain.

The immune system protects organisms against what?

  • Ground Truth Answers: diseasediseasediseasedisease

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What are the agents the immune system detects known as?

  • Ground Truth Answers: pathogenspathogenspathogenspathogens

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Which part of the immune system protects the brain?

  • Ground Truth Answers: neuroimmune systemneuroimmuneneuroimmuneneuroimmune system

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What separates the neuroimmune system and peripheral immune system in humans?

  • Ground Truth Answers: blood–brain barrier, blood–cerebrospinal fluid barrierblood–brain barrier, blood–cerebrospinal fluid barrier, and similar fluid–brain barriersblood–brain barrier, blood–cerebrospinal fluid barrier, and similar fluid–brain barriersfluid–brain barriers

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What are the agents detected by the immune system called?

  • Ground Truth Answers: pathogenspathogenspathogenspathogens

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What are the two different types of immunity?

  • Ground Truth Answers: humoral immunity versus cell-mediated immunityhumoral immunity versus cell-mediated immunityhumoral immunity versus cell-mediated immunityhumoral immunity versus cell-mediated immunity

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What are the two major subsystems of the immune system?

  • Ground Truth Answers: innate immune system versus the adaptive immune systeminnate immune system versus the adaptive immune systeminnate immune system versus the adaptive immune systeminnate immune system versus the adaptive immune system

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What is the immune system of the brained known as?

  • Ground Truth Answers: neuroimmune systemneuroimmuneneuroimmune systemneuroimmune system

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What is the system of many biological structures and processes that protect an organism from cold?

  • Ground Truth Answers: <No Answer>

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What is not an example of a pathogen?

  • Ground Truth Answers: <No Answer>

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What is the immune system unable to distinguish from healthy tissue?

  • Ground Truth Answers: <No Answer>

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What is the immune system of the stomach known as?

  • Ground Truth Answers: <No Answer>

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What connects the peripheral immune system to the neuroimmune system?

  • Ground Truth Answers: <No Answer>

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Disorders of the immune system can result in autoimmune diseases, inflammatory diseases and cancer. Immunodeficiency occurs when the immune system is less active than normal, resulting in recurring and life-threatening infections. In humans, immunodeficiency can either be the result of a genetic disease such as severe combined immunodeficiency, acquired conditions such as HIV/AIDS, or the use of immunosuppressive medication. In contrast, autoimmunity results from a hyperactive immune system attacking normal tissues as if they were foreign organisms. Common autoimmune diseases include Hashimoto's thyroiditis, rheumatoid arthritis, diabetes mellitus type 1, and systemic lupus erythematosus. Immunology covers the study of all aspects of the immune system.

What happens when the immune system less active than normal?

  • Ground Truth Answers: ImmunodeficiencyImmunodeficiencyImmunodeficiency occurs

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What is the term for a hyperactive immune system that attacks normal tissues?

  • Ground Truth Answers: autoimmunityautoimmunityautoimmunity

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What field involves the study of the immune system?

  • Ground Truth Answers: ImmunologyImmunologyImmunology

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What acquired condition results in immunodeficiency in humans?

  • Ground Truth Answers: HIV/AIDSHIV/AIDSHIV/AIDS

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What is not caused by disorders of the immune system?

  • Ground Truth Answers: <No Answer>

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What kind of medicine can cause autoimmunity?

  • Ground Truth Answers: <No Answer>

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What causes the immune system to treat foreign organisms like normal tissues?

  • Ground Truth Answers: <No Answer>

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What is not a condition that causes immunodeficiency?

  • Ground Truth Answers: <No Answer>

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What is a rare autoimmune disease?

  • Ground Truth Answers: <No Answer>

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Immunology is a science that examines the structure and function of the immune system. It originates from medicine and early studies on the causes of immunity to disease. The earliest known reference to immunity was during the plague of Athens in 430 BC. Thucydides noted that people who had recovered from a previous bout of the disease could nurse the sick without contracting the illness a second time. In the 18th century, Pierre-Louis Moreau de Maupertuis made experiments with scorpion venom and observed that certain dogs and mice were immune to this venom. This and other observations of acquired immunity were later exploited by Louis Pasteur in his development of vaccination and his proposed germ theory of disease. Pasteur's theory was in direct opposition to contemporary theories of disease, such as the miasma theory. It was not until Robert Koch's 1891 proofs, for which he was awarded a Nobel Prize in 1905, that microorganisms were confirmed as the cause of infectious disease. Viruses were confirmed as human pathogens in 1901, with the discovery of the yellow fever virus by Walter Reed.

Who won the Nobel Prize in 1905?

  • Ground Truth Answers: Robert KochRobert KochRobert Koch

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What did Robert Koch prove was the cause of infectious disease?

  • Ground Truth Answers: microorganismsmicroorganismsmicroorganisms

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What virus did Walter Reed discover?

  • Ground Truth Answers: yellow fever virusyellow feveryellow fever virus

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When was the first known historical reference to immunity?

  • Ground Truth Answers: Athens in 430 BC430 BC430 BC.

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What is a science that examines the structure and function of the brain?

  • Ground Truth Answers: <No Answer>

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When is the latest known reference to immunity?

  • Ground Truth Answers: <No Answer>

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What scientist experimented with snake venom in the 18th century?

  • Ground Truth Answers: <No Answer>

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Whose theories supported the miasma theory?

  • Ground Truth Answers: <No Answer>

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When did Robert Koch discover the yellow fever virus?

  • Ground Truth Answers: <No Answer>

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The immune system protects organisms from infection with layered defenses of increasing specificity. In simple terms, physical barriers prevent pathogens such as bacteria and viruses from entering the organism. If a pathogen breaches these barriers, the innate immune system provides an immediate, but non-specific response. Innate immune systems are found in all plants and animals. If pathogens successfully evade the innate response, vertebrates possess a second layer of protection, the adaptive immune system, which is activated by the innate response. Here, the immune system adapts its response during an infection to improve its recognition of the pathogen. This improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered.

What type of immune systems are found in all plants and animals?

  • Ground Truth Answers: Innate immune systemsInnateInnate immune systems

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What immune system is activated by the innate response?

  • Ground Truth Answers: adaptive immune systemadaptivethe adaptive immune system

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What allows the adaptive immune system to react faster and more strongly each subsequent time a pathogen is encountered?

  • Ground Truth Answers: immunological memoryimmunological memoryimmunological memory

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What is the first line of defense against pathogens that prevents them from entering an organism?

  • Ground Truth Answers: physical barriersphysical barriersphysical barriers

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What exposes organisms to infection?

  • Ground Truth Answers: <No Answer>

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What is not prevented from entering an organism?

  • Ground Truth Answers: <No Answer>

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What is activated before the innate response in vertebrates?

  • Ground Truth Answers: <No Answer>

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What is gotten rid of after a pathogen has been eliminated?

  • Ground Truth Answers: <No Answer>

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What causes the organism to attack more slowly and weakly every time a pathogen is encountered?

  • Ground Truth Answers: <No Answer>

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Both innate and adaptive immunity depend on the ability of the immune system to distinguish between self and non-self molecules. In immunology, self molecules are those components of an organism's body that can be distinguished from foreign substances by the immune system. Conversely, non-self molecules are those recognized as foreign molecules. One class of non-self molecules are called antigens (short for antibody generators) and are defined as substances that bind to specific immune receptors and elicit an immune response.

The adaptive immune system must distinguish between what types of molecules?

  • Ground Truth Answers: self and non-selfself and non-selfself and non-self molecules

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What molecules are parts of the body of an organism in immunology?

  • Ground Truth Answers: self moleculesselfself molecules

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What molecules are recognized as foreign by the immune system?

  • Ground Truth Answers: non-self moleculesnon-selfnon-self molecules

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What term is shorthand for antibody generators?

  • Ground Truth Answers: antigensantigensantigens

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Antigens bind to what in order to elicit a response of the immune system?

  • Ground Truth Answers: specific immune receptorsreceptorsspecific immune receptors

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What does not depend on the immune system's ability to distinguish between the self and others?

  • Ground Truth Answers: <No Answer>

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What is a one class of self molecule?

  • Ground Truth Answers: <No Answer>

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What can not be distinguished from foreign substances by the immune system?

  • Ground Truth Answers: <No Answer>

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What do self molecules bind to?

  • Ground Truth Answers: <No Answer>

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What happens when an antigen fails to bind to an immune receptor?

  • Ground Truth Answers: <No Answer>

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Microorganisms or toxins that successfully enter an organism encounter the cells and mechanisms of the innate immune system. The innate response is usually triggered when microbes are identified by pattern recognition receptors, which recognize components that are conserved among broad groups of microorganisms, or when damaged, injured or stressed cells send out alarm signals, many of which (but not all) are recognized by the same receptors as those that recognize pathogens. Innate immune defenses are non-specific, meaning these systems respond to pathogens in a generic way. This system does not confer long-lasting immunity against a pathogen. The innate immune system is the dominant system of host defense in most organisms.

What part of the innate immune system identifies microbes and triggers immune response?

  • Ground Truth Answers: pattern recognition receptorsreceptorscells

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For most organisms, what is the dominant system of defense?

  • Ground Truth Answers: innate immune systeminnate immune systemThe innate immune

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Pattern recognition receptors recognize components present in broad groups of what?

  • Ground Truth Answers: microorganismsmicroorganismsmicroorganisms

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The innate immune system responds in a generic way, meaning it is what?

  • Ground Truth Answers: non-specificnon-specificnon-specific

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What do toxins that fail to enter an organism encounter?

  • Ground Truth Answers: <No Answer>

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What causes the innate response to be disarmed?

  • Ground Truth Answers: <No Answer>

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What kind of cells fail to send out alarm signals?

  • Ground Truth Answers: <No Answer>

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What defenses respond to pathogens in a specific way?

  • Ground Truth Answers: <No Answer>

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What system gives an organism long lasting immunity against a pathogen?

  • Ground Truth Answers: <No Answer>

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Several barriers protect organisms from infection, including mechanical, chemical, and biological barriers. The waxy cuticle of many leaves, the exoskeleton of insects, the shells and membranes of externally deposited eggs, and skin are examples of mechanical barriers that are the first line of defense against infection. However, as organisms cannot be completely sealed from their environments, other systems act to protect body openings such as the lungs, intestines, and the genitourinary tract. In the lungs, coughing and sneezing mechanically eject pathogens and other irritants from the respiratory tract. The flushing action of tears and urine also mechanically expels pathogens, while mucus secreted by the respiratory and gastrointestinal tract serves to trap and entangle microorganisms.

What is a mechanical barrier in insects that protects the insect?

  • Ground Truth Answers: exoskeletonexoskeletonexoskeleton

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What is an example of a mechanical barrier on leaves?

  • Ground Truth Answers: The waxy cuticlewaxy cuticlewaxy cuticle

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What responses protect the lungs by mechanically ejecting pathogens from the respiratory system?

  • Ground Truth Answers: coughing and sneezingcoughing and sneezingcoughing and sneezing

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What is secreted by the respiratory tract to trap microorganisms?

  • Ground Truth Answers: mucusmucusmucus

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The flushing action of what expels pathogens from the eyes?

  • Ground Truth Answers: tearstearstears

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What kind of barrier does not protect organisms from infection?

  • Ground Truth Answers: <No Answer>

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What is an example of a chemical barrier?

  • Ground Truth Answers: <No Answer>

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What is the last line of defense against infection?

  • Ground Truth Answers: <No Answer>

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What ejects pathogens from the gastrointestinal tract?

  • Ground Truth Answers: <No Answer>

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What is not an example of a mechanical barrier?

  • Ground Truth Answers: <No Answer>

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Chemical barriers also protect against infection. The skin and respiratory tract secrete antimicrobial peptides such as the β-defensins. Enzymes such as lysozyme and phospholipase A2 in saliva, tears, and breast milk are also antibacterials. Vaginal secretions serve as a chemical barrier following menarche, when they become slightly acidic, while semen contains defensins and zinc to kill pathogens. In the stomach, gastric acid and proteases serve as powerful chemical defenses against ingested pathogens.

What are the anitmicrobial peptides secreted by the skin called?

  • Ground Truth Answers: β-defensinsβ-defensinsβ-defensins

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What enzymes in saliva are antibacterial in nature?

  • Ground Truth Answers: lysozyme and phospholipase A2lysozyme and phospholipase A2lysozyme

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Semen contains what in order to kill pathogens?

  • Ground Truth Answers: defensins and zincdefensins and zincdefensins

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What compounds in the stomach protect against ingested pathogens?

  • Ground Truth Answers: gastric acid and proteasesgastric acid and proteasesgastric acid

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Vaginal secretions serve as a chemical protective barrier following what?

  • Ground Truth Answers: menarchemenarchemenarche

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What does the respiratory tract secrete in order to promote infection?

  • Ground Truth Answers: <No Answer>

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What enzyme is not an antibacterial?

  • Ground Truth Answers: <No Answer>

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What fluids are enzymes not found in?

  • Ground Truth Answers: <No Answer>

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When do vaginal secretions become less acidic?

  • Ground Truth Answers: <No Answer>

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What provides chemical protection to pathogens?

  • Ground Truth Answers: <No Answer>

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Within the genitourinary and gastrointestinal tracts, commensal flora serve as biological barriers by competing with pathogenic bacteria for food and space and, in some cases, by changing the conditions in their environment, such as pH or available iron. This reduces the probability that pathogens will reach sufficient numbers to cause illness. However, since most antibiotics non-specifically target bacteria and do not affect fungi, oral antibiotics can lead to an "overgrowth" of fungi and cause conditions such as a vaginal candidiasis (a yeast infection). There is good evidence that re-introduction of probiotic flora, such as pure cultures of the lactobacilli normally found in unpasteurized yogurt, helps restore a healthy balance of microbial populations in intestinal infections in children and encouraging preliminary data in studies on bacterial gastroenteritis, inflammatory bowel diseases, urinary tract infection and post-surgical infections.

What serves as a biological barrier by competing for space and food in the GI tract?

  • Ground Truth Answers: commensal floracommensal floracommensal flora

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Most antibiotics target bacteria and don't affect what class of organisms?

  • Ground Truth Answers: fungifungifungi

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What probiotic flora is found in unpasteurized yogurt?

  • Ground Truth Answers: lactobacillilactobacillilactobacilli

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Commensal flora can change what specific conditions of their environment in the gastrointestinal tract?

  • Ground Truth Answers: pH or available ironpH or available ironbalance of microbial populations

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What tracts does commensal flora help pathogens thrive in?

  • Ground Truth Answers: <No Answer>

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What does not compete with commensal flora for food and space?

  • Ground Truth Answers: <No Answer>

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What medicine can lead to a decline in fungi?

  • Ground Truth Answers: <No Answer>

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What food upsets the balance of microbial populations?

  • Ground Truth Answers: <No Answer>

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What is an infection caused by an overgrowth of bacteria?

  • Ground Truth Answers: <No Answer>

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Inflammation is one of the first responses of the immune system to infection. The symptoms of inflammation are redness, swelling, heat, and pain, which are caused by increased blood flow into tissue. Inflammation is produced by eicosanoids and cytokines, which are released by injured or infected cells. Eicosanoids include prostaglandins that produce fever and the dilation of blood vessels associated with inflammation, and leukotrienes that attract certain white blood cells (leukocytes). Common cytokines include interleukins that are responsible for communication between white blood cells; chemokines that promote chemotaxis; and interferons that have anti-viral effects, such as shutting down protein synthesis in the host cell. Growth factors and cytotoxic factors may also be released. These cytokines and other chemicals recruit immune cells to the site of infection and promote healing of any damaged tissue following the removal of pathogens.

What is one of the first responses the immune system has to infection?

  • Ground Truth Answers: InflammationInflammationInflammation

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What causes the symptoms of inflammation?

  • Ground Truth Answers: increased blood flow into tissueincreased blood flow into tissueincreased blood flow into tissue

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What compounds are released by injured or infected cells, triggering inflammation?

  • Ground Truth Answers: eicosanoids and cytokineseicosanoids and cytokineseicosanoids

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Eicosanoids include what compounds that result in fever and blood vessel dilation?

  • Ground Truth Answers: prostaglandinsprostaglandinsprostaglandins

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What cytokines are responsible for communication between white blood cells?

  • Ground Truth Answers: interleukinsinterleukinsinterleukins

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What is one of the last responses of the immune system to infection?

  • Ground Truth Answers: <No Answer>

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What is not a symptom that is caused by inflammation?

  • Ground Truth Answers: <No Answer>

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What substances do healthy cells produce?

  • Ground Truth Answers: <No Answer>

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What is a rare cytokine?

  • Ground Truth Answers: <No Answer>

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What chemical keeps immune cells away from the site of infection?

  • Ground Truth Answers: <No Answer>

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Phagocytosis is an important feature of cellular innate immunity performed by cells called 'phagocytes' that engulf, or eat, pathogens or particles. Phagocytes generally patrol the body searching for pathogens, but can be called to specific locations by cytokines. Once a pathogen has been engulfed by a phagocyte, it becomes trapped in an intracellular vesicle called a phagosome, which subsequently fuses with another vesicle called a lysosome to form a phagolysosome. The pathogen is killed by the activity of digestive enzymes or following a respiratory burst that releases free radicals into the phagolysosome. Phagocytosis evolved as a means of acquiring nutrients, but this role was extended in phagocytes to include engulfment of pathogens as a defense mechanism. Phagocytosis probably represents the oldest form of host defense, as phagocytes have been identified in both vertebrate and invertebrate animals.

What type of cells engulf or eat pathogens and foreign particles?

  • Ground Truth Answers: phagocytesphagocytesphagocytes

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Phagocytes can be called to a specific location by what?

  • Ground Truth Answers: cytokinescytokinescytokines

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When a pathogen has been eaten by a phagocyte it becomes trapped in what vesicle?

  • Ground Truth Answers: phagosomephagosomephagosome

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What is formed when a phagosome fuses with a lysosome?

  • Ground Truth Answers: phagolysosomephagolysosomephagolysosome

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Phagocytosis first evolved as means of doing what?

  • Ground Truth Answers: acquiring nutrientsacquiring nutrientsacquiring nutrients

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What patrols the body looking for phagocytes?

  • Ground Truth Answers: <No Answer>

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What drives phagocytes away from specific areas?

  • Ground Truth Answers: <No Answer>

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Where does a phagocyte get stuck in a pathogen?

  • Ground Truth Answers: <No Answer>

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How does the pathogen kill the phagocyte?

  • Ground Truth Answers: <No Answer>

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What was the role of phagocytosis before it was used to acquire nutrients?

  • Ground Truth Answers: <No Answer>

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Neutrophils and macrophages are phagocytes that travel throughout the body in pursuit of invading pathogens. Neutrophils are normally found in the bloodstream and are the most abundant type of phagocyte, normally representing 50% to 60% of the total circulating leukocytes. During the acute phase of inflammation, particularly as a result of bacterial infection, neutrophils migrate toward the site of inflammation in a process called chemotaxis, and are usually the first cells to arrive at the scene of infection. Macrophages are versatile cells that reside within tissues and produce a wide array of chemicals including enzymes, complement proteins, and regulatory factors such as interleukin 1. Macrophages also act as scavengers, ridding the body of worn-out cells and other debris, and as antigen-presenting cells that activate the adaptive immune system.

What are two types of phagocytes that travel through the body to find invading pathogens?

  • Ground Truth Answers: Neutrophils and macrophagesNeutrophils and macrophagesNeutrophils and macrophages

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What are the most abundant kind of phagocyte?

  • Ground Truth Answers: NeutrophilsNeutrophilsNeutrophils

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What percentage of leukocytes do neutrophils represent?

  • Ground Truth Answers: 50% to 60%50% to 60%50% to 60%

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What is the process in which neutrophils move towards the site of inflammation called?

  • Ground Truth Answers: chemotaxischemotaxischemotaxis

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What is a regulatory factor produced by macrophages?

  • Ground Truth Answers: interleukin 1interleukin 1interleukin 1

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What are pathogens that travel through the body looking for phagocytes called?

  • Ground Truth Answers: <No Answer>

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Where are neutrophils rarely found?

  • Ground Truth Answers: <No Answer>

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What is the least abundant type of phagocyte?

  • Ground Truth Answers: <No Answer>

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What are usually the last cells to arrive at the scene of an infection?

  • Ground Truth Answers: <No Answer>

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What cell is unable to act as a scavenger?

  • Ground Truth Answers: <No Answer>

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Leukocytes (white blood cells) act like independent, single-celled organisms and are the second arm of the innate immune system. The innate leukocytes include the phagocytes (macrophages, neutrophils, and dendritic cells), mast cells, eosinophils, basophils, and natural killer cells. These cells identify and eliminate pathogens, either by attacking larger pathogens through contact or by engulfing and then killing microorganisms. Innate cells are also important mediators in the activation of the adaptive immune system.

What are white blood cells known as?

  • Ground Truth Answers: LeukocytesLeukocytesLeukocytes

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What cells are the second arm of the innate immune system?

  • Ground Truth Answers: Leukocytes (white blood cells)white blood cellswhite blood cells

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Innate cells can act as mediators in the activation of what branch of the immune system?

  • Ground Truth Answers: adaptive immune systemadaptiveadaptive immune system.

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What are three kinds of phagocytes?

  • Ground Truth Answers: macrophages, neutrophils, and dendritic cellsmacrophages, neutrophils, and dendritic cellsmacrophages, neutrophils, and dendritic cells

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What cells can't act independently?

  • Ground Truth Answers: <No Answer>

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What are leukocytes the first arm of?

  • Ground Truth Answers: <No Answer>

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What kind of cell is not an innate leukocyte?

  • Ground Truth Answers: <No Answer>

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What cells attack smaller pathogens through contact?

  • Ground Truth Answers: <No Answer>

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What are the least important mediators in the activation of the adaptive immune system?

  • Ground Truth Answers: <No Answer>

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Dendritic cells (DC) are phagocytes in tissues that are in contact with the external environment; therefore, they are located mainly in the skin, nose, lungs, stomach, and intestines. They are named for their resemblance to neuronal dendrites, as both have many spine-like projections, but dendritic cells are in no way connected to the nervous system. Dendritic cells serve as a link between the bodily tissues and the innate and adaptive immune systems, as they present antigens to T cells, one of the key cell types of the adaptive immune system.

What are the phagocytes that are located in tissues in contact with the external environment called?

  • Ground Truth Answers: Dendritic cellsDendritic cellsDendritic cells

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Dendritic cells are named that because they resemble what?

  • Ground Truth Answers: neuronal dendritesneuronal dendritesneuronal dendrites

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What are one of the key cell types of the adaptive immune system?

  • Ground Truth Answers: T cellsT cellsT cells

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Dendritic cells present antigens to what cells of the adaptive nervous system?

  • Ground Truth Answers: T cellsT cellsT cells

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What are phagocytes in tissues that only have contact with the internal environment called?

  • Ground Truth Answers: <No Answer>

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What areas are dendritic cells not found in?

  • Ground Truth Answers: <No Answer>

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What is named for its resemblance to dendritic cells?

  • Ground Truth Answers: <No Answer>

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What appearance do dendritic cells and neuronal dendrites not share?

  • Ground Truth Answers: <No Answer>

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What serves as a barrier between bodily tissues and the nervous system?

  • Ground Truth Answers: <No Answer>

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Natural killer cells, or NK cells, are a component of the innate immune system which does not directly attack invading microbes. Rather, NK cells destroy compromised host cells, such as tumor cells or virus-infected cells, recognizing such cells by a condition known as "missing self." This term describes cells with low levels of a cell-surface marker called MHC I (major histocompatibility complex) – a situation that can arise in viral infections of host cells. They were named "natural killer" because of the initial notion that they do not require activation in order to kill cells that are "missing self." For many years it was unclear how NK cells recognize tumor cells and infected cells. It is now known that the MHC makeup on the surface of those cells is altered and the NK cells become activated through recognition of "missing self". Normal body cells are not recognized and attacked by NK cells because they express intact self MHC antigens. Those MHC antigens are recognized by killer cell immunoglobulin receptors (KIR) which essentially put the brakes on NK cells.

What is one part of the innate immune system that doesn't attack microbes directly?

  • Ground Truth Answers: Natural killer cellsNatural killer cellsNatural killer cells

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Natural killer cells recognize cells that should be targeted by a condition known as what?

  • Ground Truth Answers: missing selfmissing selfmissing self

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Missing self desribes cells that only have small amounts of what cell-surface marker?

  • Ground Truth Answers: MHC I (major histocompatibility complex)MHC IMHC I (major histocompatibility complex)

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MHC antigens on normal body cells are recognized by what receptor on NK cells?

  • Ground Truth Answers: killer cell immunoglobulin receptors (KIRkiller cell immunoglobulinkiller cell immunoglobulin receptors (KIR)

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What part of the innate immune system directly attacks microbes?

  • Ground Truth Answers: <No Answer>

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What do NK cells protect?

  • Ground Truth Answers: <No Answer>

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Why are normal body cells attacked by NK cells?

  • Ground Truth Answers: <No Answer>

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How long was it clear how NK cells recognized tumors?

  • Ground Truth Answers: <No Answer>

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What accelerates NK cells?

  • Ground Truth Answers: <No Answer>

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The adaptive immune system evolved in early vertebrates and allows for a stronger immune response as well as immunological memory, where each pathogen is "remembered" by a signature antigen. The adaptive immune response is antigen-specific and requires the recognition of specific "non-self" antigens during a process called antigen presentation. Antigen specificity allows for the generation of responses that are tailored to specific pathogens or pathogen-infected cells. The ability to mount these tailored responses is maintained in the body by "memory cells". Should a pathogen infect the body more than once, these specific memory cells are used to quickly eliminate it.

In what types of organisms did the adaptive immune system first evolve?

  • Ground Truth Answers: vertebratesvertebratesearly vertebrates

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The adaptive immune system recognizes non-self antigens during a process called what?

  • Ground Truth Answers: antigen presentationantigen presentationantigen presentation

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Antigen specificity allows responses that are specific to certain types of what?

  • Ground Truth Answers: pathogens or pathogen-infected cellspathogenspathogen-infected cells

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What evolved in later vertebrates?

  • Ground Truth Answers: <No Answer>

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What immune response is not antigen-specific?

  • Ground Truth Answers: <No Answer>

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What is not needed for adaptive immune responses?

  • Ground Truth Answers: <No Answer>

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What allows for responses that are not tailored to a specific pathogen?

  • Ground Truth Answers: <No Answer>

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What is used to eliminate a pathogen that infects the body once?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Both B cells and T cells carry receptor molecules that recognize specific targets. T cells recognize a "non-self" target, such as a pathogen, only after antigens (small fragments of the pathogen) have been processed and presented in combination with a "self" receptor called a major histocompatibility complex (MHC) molecule. There are two major subtypes of T cells: the killer T cell and the helper T cell. In addition there are regulatory T cells which have a role in modulating immune response. Killer T cells only recognize antigens coupled to Class I MHC molecules, while helper T cells and regulatory T cells only recognize antigens coupled to Class II MHC molecules. These two mechanisms of antigen presentation reflect the different roles of the two types of T cell. A third, minor subtype are the γδ T cells that recognize intact antigens that are not bound to MHC receptors.

What are the two major subtypes of T cells?

  • Ground Truth Answers: killer T cell and the helper T cellkiller T cell and the helper T cellthe killer T cell and the helper T cell

  • Prediction:

What kind of T cells have the purpose of modulating the immune response?

  • Ground Truth Answers: regulatory T cellsregulatoryregulatory T cells

  • Prediction:

Killer T cells can only recognize antigens coupled to what kind of molecules?

  • Ground Truth Answers: Class I MHC moleculesClass I MHCClass I MHC molecules

  • Prediction:

Helper and regulatory T cells can only recognize antigens coupled to what kind of molecules?

  • Ground Truth Answers: Class II MHC moleculesClass II MHCClass II MHC molecules

  • Prediction:

What class of T cells recognizes intact antigens that are not associated with MHC receptors?

  • Ground Truth Answers: γδ T cellsγδγδ T cells

  • Prediction:

What cells do not carry receptor molecules?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do T cells recognize before antigens have been processed?

  • Ground Truth Answers: <No Answer>

  • Prediction:

How many subtypes of B cells exist?

  • Ground Truth Answers: <No Answer>

  • Prediction:

How many roles do the types of B cell have?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do killer B cells recognize?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Killer T cells are a sub-group of T cells that kill cells that are infected with viruses (and other pathogens), or are otherwise damaged or dysfunctional. As with B cells, each type of T cell recognizes a different antigen. Killer T cells are activated when their T cell receptor (TCR) binds to this specific antigen in a complex with the MHC Class I receptor of another cell. Recognition of this MHC:antigen complex is aided by a co-receptor on the T cell, called CD8. The T cell then travels throughout the body in search of cells where the MHC I receptors bear this antigen. When an activated T cell contacts such cells, it releases cytotoxins, such as perforin, which form pores in the target cell's plasma membrane, allowing ions, water and toxins to enter. The entry of another toxin called granulysin (a protease) induces the target cell to undergo apoptosis. T cell killing of host cells is particularly important in preventing the replication of viruses. T cell activation is tightly controlled and generally requires a very strong MHC/antigen activation signal, or additional activation signals provided by "helper" T cells (see below).

What kind of T cells kill cells that are infected with pathogens?

  • Ground Truth Answers: Killer T cellsKiller TKiller T cells

  • Prediction:

What is the receptor that killer T cells use to bind to specific antigens that are complexed with the MHC Class 1 receptor of another cell?

  • Ground Truth Answers: T cell receptor (TCR)T cell receptorT cell receptor (TCR)

  • Prediction:

What co-receptor on the T cell helps in recognizing the MHC-antigen complex?

  • Ground Truth Answers: CD8CD8CD8

  • Prediction:

When an activated killer T cell finds cells where the MHC 1 receptor has specific antigens, it releases cytotoxins such as what?

  • Ground Truth Answers: perforinperforinperforin

  • Prediction:

What toxin induces apoptosis in the target cell?

  • Ground Truth Answers: granulysingranulysingranulysin (a protease)

  • Prediction:

What cells help breed cells that are infected with viruses?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do Killer B cells kill?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When are Killer T cells deactivated?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What co-receptor makes recognition more difficult?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What allows ions, water and toxins to exit the target cell's membrane?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Helper T cells express T cell receptors (TCR) that recognize antigen bound to Class II MHC molecules. The MHC:antigen complex is also recognized by the helper cell's CD4 co-receptor, which recruits molecules inside the T cell (e.g., Lck) that are responsible for the T cell's activation. Helper T cells have a weaker association with the MHC:antigen complex than observed for killer T cells, meaning many receptors (around 200–300) on the helper T cell must be bound by an MHC:antigen in order to activate the helper cell, while killer T cells can be activated by engagement of a single MHC:antigen molecule. Helper T cell activation also requires longer duration of engagement with an antigen-presenting cell. The activation of a resting helper T cell causes it to release cytokines that influence the activity of many cell types. Cytokine signals produced by helper T cells enhance the microbicidal function of macrophages and the activity of killer T cells. In addition, helper T cell activation causes an upregulation of molecules expressed on the T cell's surface, such as CD40 ligand (also called CD154), which provide extra stimulatory signals typically required to activate antibody-producing B cells.

What co-receptor recruits molecules inside the T cell that are responsible for cell activation?

  • Ground Truth Answers: CD4 co-receptorCD4CD4 co-receptor

  • Prediction:

How many receptors on a helper T cell must be bound to a MHC:antigen complex in order for the cell to be activated?

  • Ground Truth Answers: around 200–300around 200–300around 200–300

  • Prediction:

The receptors on a killer T cell must bind to how many MHC: antigen complexes in order to activate the cell?

  • Ground Truth Answers: a single MHC:antigen moleculesinglea single MHC:antigen molecule

  • Prediction:

Activation of a helper T cell causes it to release what chemicals that influence cell activity?

  • Ground Truth Answers: cytokinescytokinescytokines

  • Prediction:

What is a ligand on the cell surface that is upregulated after helper T cell activation?

  • Ground Truth Answers: CD40 ligandCD40CD40 ligand

  • Prediction:

What antigens do Helper T cells not recognize?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What has a stronger association with the MHC:antigen complex than killer T cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are killer T cells dis-activated by?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do helper T cells absorb?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do B cells help T cells produce?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Gamma delta T cells (γδ T cells) possess an alternative T cell receptor (TCR) as opposed to CD4+ and CD8+ (αβ) T cells and share the characteristics of helper T cells, cytotoxic T cells and NK cells. The conditions that produce responses from γδ T cells are not fully understood. Like other 'unconventional' T cell subsets bearing invariant TCRs, such as CD1d-restricted Natural Killer T cells, γδ T cells straddle the border between innate and adaptive immunity. On one hand, γδ T cells are a component of adaptive immunity as they rearrange TCR genes to produce receptor diversity and can also develop a memory phenotype. On the other hand, the various subsets are also part of the innate immune system, as restricted TCR or NK receptors may be used as pattern recognition receptors. For example, large numbers of human Vγ9/Vδ2 T cells respond within hours to common molecules produced by microbes, and highly restricted Vδ1+ T cells in epithelia respond to stressed epithelial cells.

Gamma delta T cells share the characteristics of what other types of T cells?

  • Ground Truth Answers: helper T cells, cytotoxic T cells and NK cellshelper T cells, cytotoxic T cellshelper T cells

  • Prediction:

Gamma delta T cells have a different version of what receptor?

  • Ground Truth Answers: alternative T cell receptor (TCR)T cellT cell receptor (TCR)

  • Prediction:

What type of T cells help with both innnate and adaptive immunity?

  • Ground Truth Answers: γδ T cellsγδγδ T cells

  • Prediction:

Gamma delta T cells rearrange TCR genes to produce what?

  • Ground Truth Answers: receptor diversityreceptor diversityreceptor diversity

  • Prediction:

What kind of human T cells respond to common molecules produced by microbes?

  • Ground Truth Answers: Vγ9/Vδ2 T cellsVγ9/Vδ2Vγ9/Vδ2 T cells

  • Prediction:

What cells do not possess an alternative T cell receptor?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells do gamma delta T cells not share characteristics with?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is fully understood about γδ T cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What responds in small numbers to common molecules produced by microbes?

  • Ground Truth Answers: <No Answer>

  • Prediction:

A B cell identifies pathogens when antibodies on its surface bind to a specific foreign antigen. This antigen/antibody complex is taken up by the B cell and processed by proteolysis into peptides. The B cell then displays these antigenic peptides on its surface MHC class II molecules. This combination of MHC and antigen attracts a matching helper T cell, which releases lymphokines and activates the B cell. As the activated B cell then begins to divide, its offspring (plasma cells) secrete millions of copies of the antibody that recognizes this antigen. These antibodies circulate in blood plasma and lymph, bind to pathogens expressing the antigen and mark them for destruction by complement activation or for uptake and destruction by phagocytes. Antibodies can also neutralize challenges directly, by binding to bacterial toxins or by interfering with the receptors that viruses and bacteria use to infect cells.

What kind of cell identifies pathogens when the antibodies on its surface complex with a specific foreign antigen?

  • Ground Truth Answers: B cellBA B cell

  • Prediction:

What is the process by which the antigen/antibody complex is processed in to peptides?

  • Ground Truth Answers: proteolysisproteolysisproteolysis

  • Prediction:

What does the matching helper T cell release when it binds with the MHC:antigen complex of the B cell?

  • Ground Truth Answers: lymphokineslymphokineslymphokines

  • Prediction:

When does a T cell identify pathogens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are peptides processed into?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What attracts a matching helper B cell?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When do antibodies not circulate in?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What can antibodies not neutralize?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When B cells and T cells are activated and begin to replicate, some of their offspring become long-lived memory cells. Throughout the lifetime of an animal, these memory cells remember each specific pathogen encountered and can mount a strong response if the pathogen is detected again. This is "adaptive" because it occurs during the lifetime of an individual as an adaptation to infection with that pathogen and prepares the immune system for future challenges. Immunological memory can be in the form of either passive short-term memory or active long-term memory.

When B cells and T cells begin to replicate, what do some of their offspring cells become?

  • Ground Truth Answers: long-lived memory cellslong-lived memory cellslong-lived memory cells

  • Prediction:

The function of long-lived memory cells is an example of what kind of immune response?

  • Ground Truth Answers: adaptiveadaptivestrong response

  • Prediction:

Immunological memory can take what two forms?

  • Ground Truth Answers: passive short-term memory or active long-term memorypassive short-term memory or active long-term memorypassive short-term memory or active long-term memory

  • Prediction:

Long-lived memory cells can remember previous encounters with what?

  • Ground Truth Answers: specific pathogenpathogeneach specific pathogen

  • Prediction:

What happens when B cells and T cells are deactivated?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells mount a weak response if a pathogen is detected again?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not a form of immunological memory?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Why are memory cells not considered adaptive?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells are unable to remember specific pathogens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Newborn infants have no prior exposure to microbes and are particularly vulnerable to infection. Several layers of passive protection are provided by the mother. During pregnancy, a particular type of antibody, called IgG, is transported from mother to baby directly across the placenta, so human babies have high levels of antibodies even at birth, with the same range of antigen specificities as their mother. Breast milk or colostrum also contains antibodies that are transferred to the gut of the infant and protect against bacterial infections until the newborn can synthesize its own antibodies. This is passive immunity because the fetus does not actually make any memory cells or antibodies—it only borrows them. This passive immunity is usually short-term, lasting from a few days up to several months. In medicine, protective passive immunity can also be transferred artificially from one individual to another via antibody-rich serum.

Newborns are vulnerable to infection because they have no previous exposure to what?

  • Ground Truth Answers: microbesmicrobesmicrobes

  • Prediction:

What antibody is transported from the mother to baby across the placenta?

  • Ground Truth Answers: IgGIgGIgG

  • Prediction:

Antibodies are transferred to the gut of the infant through what means?

  • Ground Truth Answers: Breast milk or colostrumBreast milkBreast milk or colostrum

  • Prediction:

Antibodies transported from the mother to an infant via the placenta is an example of what type of short-lived immunity?

  • Ground Truth Answers: passive immunitypassivepassive immunity

  • Prediction:

What people are least vulnerable to infection?

  • Ground Truth Answers: <No Answer>

  • Prediction:

How many layers of protection are provided by the father?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What antibody is transmitted from the father to the baby?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not present in breast milk?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not possible to transfer from one person to another artificially?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Hormones can act as immunomodulators, altering the sensitivity of the immune system. For example, female sex hormones are known immunostimulators of both adaptive and innate immune responses. Some autoimmune diseases such as lupus erythematosus strike women preferentially, and their onset often coincides with puberty. By contrast, male sex hormones such as testosterone seem to be immunosuppressive. Other hormones appear to regulate the immune system as well, most notably prolactin, growth hormone and vitamin D.

Hormones can alter the sensitivity of the immune system, so they can be referred to as what?

  • Ground Truth Answers: immunomodulatorsimmunomodulatorsimmunomodulators

  • Prediction:

Female sex hormones are immunostimulators of which immune responses?

  • Ground Truth Answers: adaptive and innate immune responsesboth adaptive and innateadaptive and innate immune responses

  • Prediction:

What is an autoimmune disease that affects women preferentially?

  • Ground Truth Answers: lupus erythematosuslupus erythematosuslupus erythematosus

  • Prediction:

What is the effect of testosterone on the male immune system?

  • Ground Truth Answers: immunosuppressiveimmunosuppressiveimmunosuppressive

  • Prediction:

What keeps the sensitivity of the immune system at the same levels?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When do autoimmune diseases often strike men?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is a hormone that does not effect the immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What male sex hormone is an immunostimulator?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is an autoimmune disease that mostly strikes men?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When suffering from sleep deprivation, active immunizations may have a diminished effect and may result in lower antibody production, and a lower immune response, than would be noted in a well-rested individual. Additionally, proteins such as NFIL3, which have been shown to be closely intertwined with both T-cell differentiation and our circadian rhythms, can be affected through the disturbance of natural light and dark cycles through instances of sleep deprivation, shift work, etc. As a result, these disruptions can lead to an increase in chronic conditions such as heart disease, chronic pain, and asthma.

What is a protein that is closely intertwined with circadian rhythms?

  • Ground Truth Answers: NFIL3NFIL3NFIL3

  • Prediction:

Disruptions in sleep can lead to increase in what chronic conditions?

  • Ground Truth Answers: heart disease, chronic pain, and asthmaheart disease, chronic pain, and asthmachronic pain

  • Prediction:

What kind of deprivation results in diminished immune response and lower antibody production?

  • Ground Truth Answers: sleep deprivationsleepsleep deprivation

  • Prediction:

What has a stronger effect during sleep deprivation?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When is antibody production higher than normal?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What protein does not effect T-cell differentiation?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What chronic conditions can cause sleep deprivation?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not effected by natural light and dark cycles?

  • Ground Truth Answers: <No Answer>

  • Prediction:

It is conjectured that a progressive decline in hormone levels with age is partially responsible for weakened immune responses in aging individuals. Conversely, some hormones are regulated by the immune system, notably thyroid hormone activity. The age-related decline in immune function is also related to decreasing vitamin D levels in the elderly. As people age, two things happen that negatively affect their vitamin D levels. First, they stay indoors more due to decreased activity levels. This means that they get less sun and therefore produce less cholecalciferol via UVB radiation. Second, as a person ages the skin becomes less adept at producing vitamin D.

What is partially responsible for weakened immune response in older individuals?

  • Ground Truth Answers: decline in hormone levels with agedecline in hormone levelsdecline in hormone levels

  • Prediction:

As a person gets older, what does the skin produce less of?

  • Ground Truth Answers: vitamin Dvitamin Dvitamin D.

  • Prediction:

The production of what signalling molecules is regulated by the immune system?

  • Ground Truth Answers: hormoneshormoneshormones

  • Prediction:

Older people get less sun and produce less of what chemical via UVB radiation?

  • Ground Truth Answers: cholecalciferolcholecalciferolcholecalciferol

  • Prediction:

What increases with age?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do increased hormone levels cause in aging adults?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What hormones are independent from the immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What causes elevated vitamin D levels in the elderly?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What becomes more adept at producing vitamin D as a person ages?

  • Ground Truth Answers: <No Answer>

  • Prediction:

The main response of the immune system to tumors is to destroy the abnormal cells using killer T cells, sometimes with the assistance of helper T cells. Tumor antigens are presented on MHC class I molecules in a similar way to viral antigens. This allows killer T cells to recognize the tumor cell as abnormal. NK cells also kill tumorous cells in a similar way, especially if the tumor cells have fewer MHC class I molecules on their surface than normal; this is a common phenomenon with tumors. Sometimes antibodies are generated against tumor cells allowing for their destruction by the complement system.

What type of immune cells help to destroy abnormal cells in tumors?

  • Ground Truth Answers: killer T cellskiller T cellskiller T cells

  • Prediction:

Lots of tumor cells have fewer of what type of molecule on their surface?

  • Ground Truth Answers: MHC class I moleculesMHC class IMHC class I molecules

  • Prediction:

Tumor antigens are complexed with MHC class I molecules in the same way as what antigens?

  • Ground Truth Answers: viral antigensviralviral antigens

  • Prediction:

The immune system also produces what molecules in order to allow for tumor destruction by the complement system?

  • Ground Truth Answers: antibodiesantibodiesantibodies

  • Prediction:

What cells are used to multiply the abnormal cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells do helper B cells assist?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What antigens present differently than viral antigens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do helper T cells recognize killer T cells as?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are antibodies never generated to fight?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Unlike animals, plants lack phagocytic cells, but many plant immune responses involve systemic chemical signals that are sent through a plant. Individual plant cells respond to molecules associated with pathogens known as Pathogen-associated molecular patterns or PAMPs. When a part of a plant becomes infected, the plant produces a localized hypersensitive response, whereby cells at the site of infection undergo rapid apoptosis to prevent the spread of the disease to other parts of the plant. Systemic acquired resistance (SAR) is a type of defensive response used by plants that renders the entire plant resistant to a particular infectious agent. RNA silencing mechanisms are particularly important in this systemic response as they can block virus replication.

Plants lack what kind of immune cells?

  • Ground Truth Answers: phagocytic cellsphagocyticphagocytic cells

  • Prediction:

Plant cells respond to the molecules associated with pathogens known as what?

  • Ground Truth Answers: Pathogen-associated molecular patternsPathogen-associated molecular patternsPathogen-associated molecular patterns or PAMPs

  • Prediction:

Cells of the site of an infection in a plant undergo what process to prevent spread of the disease?

  • Ground Truth Answers: apoptosisapoptosisrapid apoptosis

  • Prediction:

What is a kind of defense response that makes the entire plant resistant to a particular agent?

  • Ground Truth Answers: Systemic acquired resistance (SAR)Systemic acquired resistanceSystemic acquired resistance (SAR)

  • Prediction:

What is a mechanism that can help plants block virus replication?

  • Ground Truth Answers: RNA silencing mechanismsRNA silencing mechanismsRNA silencing mechanisms

  • Prediction:

What cells do plants and animals both have?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What happens when all parts of a plant become infected?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do cells away from the site of the infection undergo?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells undergo slow apoptosis?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is unimportant in SAR?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Overactive immune responses comprise the other end of immune dysfunction, particularly the autoimmune disorders. Here, the immune system fails to properly distinguish between self and non-self, and attacks part of the body. Under normal circumstances, many T cells and antibodies react with "self" peptides. One of the functions of specialized cells (located in the thymus and bone marrow) is to present young lymphocytes with self antigens produced throughout the body and to eliminate those cells that recognize self-antigens, preventing autoimmunity.

What kind of disorders are the result of an overactive immune response?

  • Ground Truth Answers: autoimmune disordersautoimmuneautoimmune disorders

  • Prediction:

In autoimmune disorders, the immune system doesn't distinguish between what types of cells?

  • Ground Truth Answers: self and non-selfself and non-selfself and non-self

  • Prediction:

Where are the specialized cells that eliminate cells that recognize self-antigens located?

  • Ground Truth Answers: thymus and bone marrowthymus and bone marrowthymus and bone marrow

  • Prediction:

Under normal conditions, T cells and antibodies produce what kind of peptides?

  • Ground Truth Answers: "self" peptidesselfself" peptides

  • Prediction:

What disorder causes the immune system to distinguish between self and non-self?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cell never reacts with self peptides?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is the function of specialize cells located in the brain?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells are not eliminated by the immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Where are specialized cells not located?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Immunodeficiencies occur when one or more of the components of the immune system are inactive. The ability of the immune system to respond to pathogens is diminished in both the young and the elderly, with immune responses beginning to decline at around 50 years of age due to immunosenescence. In developed countries, obesity, alcoholism, and drug use are common causes of poor immune function. However, malnutrition is the most common cause of immunodeficiency in developing countries. Diets lacking sufficient protein are associated with impaired cell-mediated immunity, complement activity, phagocyte function, IgA antibody concentrations, and cytokine production. Additionally, the loss of the thymus at an early age through genetic mutation or surgical removal results in severe immunodeficiency and a high susceptibility to infection.

What kind of disorders occur when part of the immune system isn't active?

  • Ground Truth Answers: ImmunodeficienciesImmunodeficienciesImmunodeficiencies

  • Prediction:

In what two age groups is the strength of the immune system reduced?

  • Ground Truth Answers: the young and the elderlythe young and the elderlyyoung and the elderly

  • Prediction:

At what age do immune responses typically begin to decline?

  • Ground Truth Answers: around 50 years of age50around 50 years of age

  • Prediction:

What are some causes of reduced immune function in developed countries?

  • Ground Truth Answers: obesity, alcoholism, and drug useobesity, alcoholism, and drug useobesity, alcoholism, and drug use

  • Prediction:

What is the most common cause of immunodeficiency in developing nations?

  • Ground Truth Answers: malnutritionmalnutritionmalnutrition

  • Prediction:

What occurs when all components of the immune system are active?

  • Ground Truth Answers: <No Answer>

  • Prediction:

In what people is the immune system the strongest?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is the rarest cause of poor immune function in developing countries?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do diets with too much protein cause?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does the loss of the thymus at an early age prevent?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Long-term active memory is acquired following infection by activation of B and T cells. Active immunity can also be generated artificially, through vaccination. The principle behind vaccination (also called immunization) is to introduce an antigen from a pathogen in order to stimulate the immune system and develop specific immunity against that particular pathogen without causing disease associated with that organism. This deliberate induction of an immune response is successful because it exploits the natural specificity of the immune system, as well as its inducibility. With infectious disease remaining one of the leading causes of death in the human population, vaccination represents the most effective manipulation of the immune system mankind has developed.

By what process can active immunity be generated in an artificial manner?

  • Ground Truth Answers: vaccinationvaccinationvaccination

  • Prediction:

What is the process of vaccination also known as?

  • Ground Truth Answers: immunizationimmunizationimmunization

  • Prediction:

In the process of vaccination, what is introduced in order to develop a specific immunity?

  • Ground Truth Answers: an antigen from a pathogenantigenantigen from a pathogen

  • Prediction:

Vaccination exploits what feature of the human immune system in order to be successful?

  • Ground Truth Answers: natural specificity of the immune systemnatural specificitythe natural specificity

  • Prediction:

When is short-term active memory acquired?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cells do not play a role in long-term active memory?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What artificial method of spreading immunity causes disease?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does vaccination not exploit?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is one of the least common causes of death in humans?

  • Ground Truth Answers: <No Answer>

  • Prediction:

The success of any pathogen depends on its ability to elude host immune responses. Therefore, pathogens evolved several methods that allow them to successfully infect a host, while evading detection or destruction by the immune system. Bacteria often overcome physical barriers by secreting enzymes that digest the barrier, for example, by using a type II secretion system. Alternatively, using a type III secretion system, they may insert a hollow tube into the host cell, providing a direct route for proteins to move from the pathogen to the host. These proteins are often used to shut down host defenses.

Bacteria often secrete what kind of proteins to ingest a physical barrier?

  • Ground Truth Answers: enzymesenzymesenzymes

  • Prediction:

What kind of system of infection involves inserting a hollow tube into a host cell?

  • Ground Truth Answers: type III secretion systemtype III secretion systemtype III secretion system

  • Prediction:

In a type III secretion system, proteins are transported to the host cell in order to do what?

  • Ground Truth Answers: shut down host defensesshut down host defensesshut down host defenses.

  • Prediction:

The success of pathogens is predicated on their ability to do what?

  • Ground Truth Answers: elude host immune responseselude host immune responsesability to elude host immune responses

  • Prediction:

What does the failure of a pathogen depend on?

  • Ground Truth Answers: <No Answer>

  • Prediction:

How do viruses overcome physical barriers?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do bacteria use to move proteins from the host to the pathogen?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are bacteria unable to secrete?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is used to shut down pathogen defenses?

  • Ground Truth Answers: <No Answer>

  • Prediction:

In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential.

Who formulated the idea of clonal selection theory of immunity?

  • Ground Truth Answers: Frank BurnetFrank BurnetFrank Burnet

  • Prediction:

What are two examples of nonself entities in accordance with Frank Burnet's theory?

  • Ground Truth Answers: pathogens, an allograftpathogens, an allograftpathogens, an allograft

  • Prediction:

What is the complex "two-signal" activation of T cells referred to?

  • Ground Truth Answers: histocompatibilityhistocompatibilityhistocompatibility

  • Prediction:

What other scientist influence Frank Burnet when he was formulating his theory of immunity?

  • Ground Truth Answers: Niels JerneNiels JerneNiels Jerne

  • Prediction:

What theory did Niels Jerne formulate?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Who did Frank Burnet inspire with a suggestion?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What theory of immunity is no longer influential?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What did Jerne develop on the basis of CST?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What did Frank Burnet formulate before the 1950s?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Anti-inflammatory drugs are often used to control the effects of inflammation. Glucocorticoids are the most powerful of these drugs; however, these drugs can have many undesirable side effects, such as central obesity, hyperglycemia, osteoporosis, and their use must be tightly controlled. Lower doses of anti-inflammatory drugs are often used in conjunction with cytotoxic or immunosuppressive drugs such as methotrexate or azathioprine. Cytotoxic drugs inhibit the immune response by killing dividing cells such as activated T cells. However, the killing is indiscriminate and other constantly dividing cells and their organs are affected, which causes toxic side effects. Immunosuppressive drugs such as cyclosporin prevent T cells from responding to signals correctly by inhibiting signal transduction pathways.

What are the most powerful class of anti-inflammatory drugs?

  • Ground Truth Answers: GlucocorticoidsGlucocorticoidsGlucocorticoids

  • Prediction:

Low doses of anti-inflammatories are sometimes used with what classes of drugs?

  • Ground Truth Answers: cytotoxic or immunosuppressive drugscytotoxic or immunosuppressiveCytotoxic drugs

  • Prediction:

What are two examples of cytotoxic or immunosuppressive drugs?

  • Ground Truth Answers: methotrexate or azathioprinemethotrexate or azathioprinemethotrexate or azathioprine

  • Prediction:

What is an example of an immunosuppressive drug that prevents T cell activity by altering signal transduction pathways?

  • Ground Truth Answers: cyclosporincyclosporincyclosporin

  • Prediction:

What is used to enhance the effects of inflammation?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are the least powerful anti-inflammatory drugs?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not a side effect of glucocorticoids?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are higher doses of anti-inflammatory drugs used with?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What drugs help T cells respond to signals correctly?

  • Ground Truth Answers: <No Answer>

  • Prediction:

In contrast, during wake periods differentiated effector cells, such as cytotoxic natural killer cells and CTLs (cytotoxic T lymphocytes), peak in order to elicit an effective response against any intruding pathogens. As well during awake active times, anti-inflammatory molecules, such as cortisol and catecholamines, peak. There are two theories as to why the pro-inflammatory state is reserved for sleep time. First, inflammation would cause serious cognitive and physical impairments if it were to occur during wake times. Second, inflammation may occur during sleep times due to the presence of melatonin. Inflammation causes a great deal of oxidative stress and the presence of melatonin during sleep times could actively counteract free radical production during this time.

What are examples of differentiated effector cells that peak during wake periods?

  • Ground Truth Answers: cytotoxic natural killer cells and CTLs (cytotoxic T lymphocytes)cytotoxic natural killer cells and CTLscytotoxic natural killer cells and CTLs (cytotoxic T lymphocytes)

  • Prediction:

What are two anti-inflammatory molecules that peak during awake hours?

  • Ground Truth Answers: cortisol and catecholaminescortisol and catecholaminescortisol and catecholamines

  • Prediction:

Inflammation occurs during sleep times because of the presence of what molecule?

  • Ground Truth Answers: melatoninmelatoninmelatonin

  • Prediction:

Melatonin during sleep can actively counteract the production of what?

  • Ground Truth Answers: free radical productionfree radicalfree radical production

  • Prediction:

What cells are at their lowest while people are awake?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Why do differentiated effector cells ebb during wake periods?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What molecules that promote inflammation peak during waking hours?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What could inflammation do during sleep periods?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What could promote free radical production during sleep times?

  • Ground Truth Answers: <No Answer>

  • Prediction:

When a T-cell encounters a foreign pathogen, it extends a vitamin D receptor. This is essentially a signaling device that allows the T-cell to bind to the active form of vitamin D, the steroid hormone calcitriol. T-cells have a symbiotic relationship with vitamin D. Not only does the T-cell extend a vitamin D receptor, in essence asking to bind to the steroid hormone version of vitamin D, calcitriol, but the T-cell expresses the gene CYP27B1, which is the gene responsible for converting the pre-hormone version of vitamin D, calcidiol into the steroid hormone version, calcitriol. Only after binding to calcitriol can T-cells perform their intended function. Other immune system cells that are known to express CYP27B1 and thus activate vitamin D calcidiol, are dendritic cells, keratinocytes and macrophages.

What does a T cell extend when it encounters a foreign pathogen?

  • Ground Truth Answers: a vitamin D receptorextends a vitamin D receptorvitamin D receptor

  • Prediction:

What is the active form of vitamin D known as?

  • Ground Truth Answers: calcitriolcalcitriolsteroid hormone calcitriol

  • Prediction:

What is the nature of the relationship between T-cells and vitamin D?

  • Ground Truth Answers: symbiotic relationshipsymbioticsymbiotic relationship

  • Prediction:

What gene is responsible for converting calcidiol into calcitriol?

  • Ground Truth Answers: gene CYP27B1CYP27B1gene CYP27B1

  • Prediction:

Other than T cells, what other immune cells express CYP27B1?

  • Ground Truth Answers: dendritic cells, keratinocytes and macrophagesdendritic cells, keratinocytes and macrophagesdendritic cells

  • Prediction:

What does a pathogen do when it encounters a T-cell?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What cell binds to vitamin C?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What vitamin do T-cells have a parasitic relationship with?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What gene is expressed by the B-cell?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What gene converts calcitriol into calcidiol?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Pattern recognition receptors are proteins used by nearly all organisms to identify molecules associated with pathogens. Antimicrobial peptides called defensins are an evolutionarily conserved component of the innate immune response found in all animals and plants, and represent the main form of invertebrate systemic immunity. The complement system and phagocytic cells are also used by most forms of invertebrate life. Ribonucleases and the RNA interference pathway are conserved across all eukaryotes, and are thought to play a role in the immune response to viruses.

What are the proteins that organisms use to identify molecules associated with pathogens?

  • Ground Truth Answers: Pattern recognition receptorsPattern recognition receptorsPattern recognition receptors

  • Prediction:

What are the antimicrobial peptides that are the main form of invertebrate systemic immunity called?

  • Ground Truth Answers: defensinsdefensinsdefensins

  • Prediction:

What cell type is also used for immune response in most types of invertebrate life?

  • Ground Truth Answers: phagocytic cellsphagocyticphagocytic cells

  • Prediction:

What pathway that plays a role in immune response to viruses is present in all eukaryotes?

  • Ground Truth Answers: RNA interference pathwayRNA interferenceRNA interference pathway

  • Prediction:

What proteins are used by very few organisms?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are peptides that help microbes flourish called?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not used by any form of invertebrate?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does not play a role in the immune response to viruses?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Where are ribonucleases not conserved?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Evolution of the adaptive immune system occurred in an ancestor of the jawed vertebrates. Many of the classical molecules of the adaptive immune system (e.g., immunoglobulins and T cell receptors) exist only in jawed vertebrates. However, a distinct lymphocyte-derived molecule has been discovered in primitive jawless vertebrates, such as the lamprey and hagfish. These animals possess a large array of molecules called Variable lymphocyte receptors (VLRs) that, like the antigen receptors of jawed vertebrates, are produced from only a small number (one or two) of genes. These molecules are believed to bind pathogenic antigens in a similar way to antibodies, and with the same degree of specificity.

What molecules of the adaptive immune system only exist in jawed vertebrates?

  • Ground Truth Answers: immunoglobulins and T cell receptorsimmunoglobulins and T cell receptorsimmunoglobulins

  • Prediction:

What are two examples of primitive jawless vertebrates?

  • Ground Truth Answers: the lamprey and hagfishlamprey and hagfishthe lamprey and hagfish

  • Prediction:

Primitive jawless vertebrates possess an array of receptors referred to as what?

  • Ground Truth Answers: Variable lymphocyte receptors (VLRs)Variable lymphocyte receptorsVariable lymphocyte receptors (VLRs)

  • Prediction:

Evolution of what part of the immune system occurred in the evolutionary ancestor of jawed vertebrates?

  • Ground Truth Answers: adaptive immune systemadaptivethe adaptive immune system

  • Prediction:

What evolved in modern jawed vertebrates?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What only exists outside of jawed vertebrates?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What primitive jawed vertebrates do not contain lymphocyte-derived molecules?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What are produced from a large number of genes?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What molecules are repelled by pathogenic antigens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

It is likely that a multicomponent, adaptive immune system arose with the first vertebrates, as invertebrates do not generate lymphocytes or an antibody-based humoral response. Many species, however, utilize mechanisms that appear to be precursors of these aspects of vertebrate immunity. Immune systems appear even in the structurally most simple forms of life, with bacteria using a unique defense mechanism, called the restriction modification system to protect themselves from viral pathogens, called bacteriophages. Prokaryotes also possess acquired immunity, through a system that uses CRISPR sequences to retain fragments of the genomes of phage that they have come into contact with in the past, which allows them to block virus replication through a form of RNA interference. Offensive elements of the immune systems are also present in unicellular eukaryotes, but studies of their roles in defense are few.

Invertebrates do not generate what type of cells that are a part of the vertebrate adaptive immune system?

  • Ground Truth Answers: lymphocyteslymphocyteslymphocytes

  • Prediction:

What is the main defense mechanism of bacteria known as?

  • Ground Truth Answers: the restriction modification systemrestriction modification systemrestriction modification system

  • Prediction:

The restriction modification system is used by bacteria for protection from what pathogens?

  • Ground Truth Answers: bacteriophagesviralbacteriophages

  • Prediction:

What is the system by which prokaryotes retain phage gene fragments that they have previously come in contact with?

  • Ground Truth Answers: CRISPRCRISPR sequencesCRISPR

  • Prediction:

Where is it unlikely that the first multicomponent, adaptive immune system arose?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What arose in the latest vertebrates?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What mechanisms do many species not utilize?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What kind of immunity do prokaryotes not have?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What has often been studied in unicellular eukaryotes?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Immunology is strongly experimental in everyday practice but is also characterized by an ongoing theoretical attitude. Many theories have been suggested in immunology from the end of the nineteenth century up to the present time. The end of the 19th century and the beginning of the 20th century saw a battle between "cellular" and "humoral" theories of immunity. According to the cellular theory of immunity, represented in particular by Elie Metchnikoff, it was cells – more precisely, phagocytes – that were responsible for immune responses. In contrast, the humoral theory of immunity, held, among others, by Robert Koch and Emil von Behring, stated that the active immune agents were soluble components (molecules) found in the organism’s “humors” rather than its cells.

What were the two main theories of immunity at the end of the 19th century?

  • Ground Truth Answers: "cellular" and "humoral" theories of immunity"cellular" and "humoral""cellular" and "humoral" theories

  • Prediction:

Who was the main proponent of the cellular theory of immunity?

  • Ground Truth Answers: Elie MetchnikoffElie MetchnikoffElie Metchnikoff

  • Prediction:

Under Elie Metchnikoff's cellular theory, what cells were responsible for immune response?

  • Ground Truth Answers: phagocytesphagocytesphagocytes

  • Prediction:

What two scientists were proponents of the humoral theory of immunity?

  • Ground Truth Answers: Robert Koch and Emil von BehringRobert Koch and Emil von BehringRobert Koch and Emil von Behring,

  • Prediction:

According to the humoral theory of immunity, what were the bodies immune agents?

  • Ground Truth Answers: soluble components (molecules)soluble componentssoluble components (molecules)

  • Prediction:

What was suggested in immunology before the 19th century?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Who was the main detractor of the cellular theory of immunity?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Who were the main detractors of the humoral theory of immunity?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What did cellular theory claim was in an organism's humors?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Clearly, some tumors evade the immune system and go on to become cancers. Tumor cells often have a reduced number of MHC class I molecules on their surface, thus avoiding detection by killer T cells. Some tumor cells also release products that inhibit the immune response; for example by secreting the cytokine TGF-β, which suppresses the activity of macrophages and lymphocytes. In addition, immunological tolerance may develop against tumor antigens, so the immune system no longer attacks the tumor cells.

Tumors that are able to evade the body's immune response can become what?

  • Ground Truth Answers: cancerscancerscancers

  • Prediction:

What receptors do tumor cells often have reduced concentrations of?

  • Ground Truth Answers: MHC class I moleculesMHC class IMHC class I molecules

  • Prediction:

What is a chemical secreted by tumors that suppresses the immune response?

  • Ground Truth Answers: cytokine TGF-βcytokine TGF-βcytokine TGF-β

  • Prediction:

Cytokine TBF-B suppresses the activity of what cell types?

  • Ground Truth Answers: macrophages and lymphocytesmacrophages and lymphocytesmacrophages and lymphocytes

  • Prediction:

What is unable to evade the immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What makes detection by killer T cells more likely?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do tumor cells release that strengthens the immune response?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does cytokine TGF-β encourage the activity of?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What happens when the immune system loses tolerance for tumor antigens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Hypersensitivity is an immune response that damages the body's own tissues. They are divided into four classes (Type I – IV) based on the mechanisms involved and the time course of the hypersensitive reaction. Type I hypersensitivity is an immediate or anaphylactic reaction, often associated with allergy. Symptoms can range from mild discomfort to death. Type I hypersensitivity is mediated by IgE, which triggers degranulation of mast cells and basophils when cross-linked by antigen. Type II hypersensitivity occurs when antibodies bind to antigens on the patient's own cells, marking them for destruction. This is also called antibody-dependent (or cytotoxic) hypersensitivity, and is mediated by IgG and IgM antibodies. Immune complexes (aggregations of antigens, complement proteins, and IgG and IgM antibodies) deposited in various tissues trigger Type III hypersensitivity reactions. Type IV hypersensitivity (also known as cell-mediated or delayed type hypersensitivity) usually takes between two and three days to develop. Type IV reactions are involved in many autoimmune and infectious diseases, but may also involve contact dermatitis (poison ivy). These reactions are mediated by T cells, monocytes, and macrophages.

What is the name for a response of the immune system that damages the body's native tissues?

  • Ground Truth Answers: HypersensitivityHypersensitivityHypersensitivity

  • Prediction:

How many classes of immune hypersensitivity are there?

  • Ground Truth Answers: four classes (Type I – IV)fourfour classes

  • Prediction:

What type of hypersensitivity is associated with allergies?

  • Ground Truth Answers: Type IType IType I hypersensitivity

  • Prediction:

What is the chemical that mediates Type 1 hypersensitivity?

  • Ground Truth Answers: IgEIgEIgE

  • Prediction:

Antibody-dependent hypersensitivity belongs to what class of hypersensitivity?

  • Ground Truth Answers: Type II hypersensitivityType IIType II hypersensitivity

  • Prediction:

What is an immune response that heals the body's own tissues?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is divided into five classes?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not a symptom of type I hypersensitivity?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What type of hypersensitivity takes between two and three weeks to develop?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What occurs when antibodies will not bind to the patient's cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

An evasion strategy used by several pathogens to avoid the innate immune system is to hide within the cells of their host (also called intracellular pathogenesis). Here, a pathogen spends most of its life-cycle inside host cells, where it is shielded from direct contact with immune cells, antibodies and complement. Some examples of intracellular pathogens include viruses, the food poisoning bacterium Salmonella and the eukaryotic parasites that cause malaria (Plasmodium falciparum) and leishmaniasis (Leishmania spp.). Other bacteria, such as Mycobacterium tuberculosis, live inside a protective capsule that prevents lysis by complement. Many pathogens secrete compounds that diminish or misdirect the host's immune response. Some bacteria form biofilms to protect themselves from the cells and proteins of the immune system. Such biofilms are present in many successful infections, e.g., the chronic Pseudomonas aeruginosa and Burkholderia cenocepacia infections characteristic of cystic fibrosis. Other bacteria generate surface proteins that bind to antibodies, rendering them ineffective; examples include Streptococcus (protein G), Staphylococcus aureus (protein A), and Peptostreptococcus magnus (protein L).

What is the process by which pathogens evade the immune system by hiding inside the host cells called?

  • Ground Truth Answers: intracellular pathogenesisintracellular pathogenesisintracellular pathogenesis

  • Prediction:

What food bacteria is an example of intracellular pathogenesis?

  • Ground Truth Answers: SalmonellaSalmonellaSalmonella

  • Prediction:

What is the eukaryotic parasite responsible for malaria known as?

  • Ground Truth Answers: Plasmodium falciparumPlasmodium falciparumPlasmodium falciparum

  • Prediction:

What bacteria lives inside a protective capsule that serves to prevent cell lysis?

  • Ground Truth Answers: Mycobacterium tuberculosisMycobacterium tuberculosisMycobacterium tuberculosis

  • Prediction:

What protein does Staphylococcus aureus produce to make antibodies ineffective?

  • Ground Truth Answers: protein AGStreptococcus (protein G)

  • Prediction:

What strategy is used by pathogens to encounter the innate immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is it called when a pathogen spends most of its lifecycle outside of host cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Where does a pathogen come in direct contact with immune cells, antibodies and complement?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What secretes pathogens that enhance the host's immune response?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do bacterial surface proteins not bind to?

  • Ground Truth Answers: <No Answer>

  • Prediction:

The mechanisms used to evade the adaptive immune system are more complicated. The simplest approach is to rapidly change non-essential epitopes (amino acids and/or sugars) on the surface of the pathogen, while keeping essential epitopes concealed. This is called antigenic variation. An example is HIV, which mutates rapidly, so the proteins on its viral envelope that are essential for entry into its host target cell are constantly changing. These frequent changes in antigens may explain the failures of vaccines directed at this virus. The parasite Trypanosoma brucei uses a similar strategy, constantly switching one type of surface protein for another, allowing it to stay one step ahead of the antibody response. Masking antigens with host molecules is another common strategy for avoiding detection by the immune system. In HIV, the envelope that covers the virion is formed from the outermost membrane of the host cell; such "self-cloaked" viruses make it difficult for the immune system to identify them as "non-self" structures.

What is the process by which the adaptive immune system is evaded by the chainging of non-essential epitopes called?

  • Ground Truth Answers: antigenic variationantigenic variationantigenic variation

  • Prediction:

What is an example of a virus that uses antigenic variation?

  • Ground Truth Answers: HIVHIVHIV

  • Prediction:

What is an example of a parasite that used the antigenic variation strategy to evade destruction?

  • Ground Truth Answers: Trypanosoma bruceiTrypanosoma bruceiTrypanosoma brucei

  • Prediction:

What compounds can be masked with the molecules of the host cell in order for a virus to evade detection?

  • Ground Truth Answers: antigensantigensantigens

  • Prediction:

What are the less complex mechanisms used to do?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is the most complex way to avoid the adaptive immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is a pathogen that does not use antigenic variation?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does not explain the failure of vaccines directed at the HIV virus?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is a parasite that always uses the same surface protein?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Another important role of the immune system is to identify and eliminate tumors. This is called immune surveillance. The transformed cells of tumors express antigens that are not found on normal cells. To the immune system, these antigens appear foreign, and their presence causes immune cells to attack the transformed tumor cells. The antigens expressed by tumors have several sources; some are derived from oncogenic viruses like human papillomavirus, which causes cervical cancer, while others are the organism's own proteins that occur at low levels in normal cells but reach high levels in tumor cells. One example is an enzyme called tyrosinase that, when expressed at high levels, transforms certain skin cells (e.g. melanocytes) into tumors called melanomas. A third possible source of tumor antigens are proteins normally important for regulating cell growth and survival, that commonly mutate into cancer inducing molecules called oncogenes.

What is the process by which the immune system identifies tumors called?

  • Ground Truth Answers: immune surveillanceimmune surveillanceimmune surveillance

  • Prediction:

What is the virus in humans that causes cervical cancer?

  • Ground Truth Answers: human papillomavirushuman papillomavirushuman papillomavirus

  • Prediction:

What is an example of an enzyme that can transform skin cells into tumors when expressed at high levels?

  • Ground Truth Answers: tyrosinasetyrosinasetyrosinase

  • Prediction:

What are cancerous tumors of the skin known as?

  • Ground Truth Answers: melanomasmelanomasmelanomas

  • Prediction:

What are the skin cells that can be transformed into tumors known as?

  • Ground Truth Answers: melanocytesmelanocytesmelanocytes

  • Prediction:

What is not an important role of the immune system?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do tumors express that are also found on normal cells?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not a cause of tumor antigens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What happens when tyrosinase is expressed at low levels?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is a fourth possible source for tumor antigens?

  • Ground Truth Answers: <No Answer>

  • Prediction:

Larger drugs (>500 Da) can provoke a neutralizing immune response, particularly if the drugs are administered repeatedly, or in larger doses. This limits the effectiveness of drugs based on larger peptides and proteins (which are typically larger than 6000 Da). In some cases, the drug itself is not immunogenic, but may be co-administered with an immunogenic compound, as is sometimes the case for Taxol. Computational methods have been developed to predict the immunogenicity of peptides and proteins, which are particularly useful in designing therapeutic antibodies, assessing likely virulence of mutations in viral coat particles, and validation of proposed peptide-based drug treatments. Early techniques relied mainly on the observation that hydrophilic amino acids are overrepresented in epitope regions than hydrophobic amino acids; however, more recent developments rely on machine learning techniques using databases of existing known epitopes, usually on well-studied virus proteins, as a training set. A publicly accessible database has been established for the cataloguing of epitopes from pathogens known to be recognizable by B cells. The emerging field of bioinformatics-based studies of immunogenicity is referred to as immunoinformatics. Immunoproteomics is the study of large sets of proteins (proteomics) involved in the immune response.

At what size and larger can drugs elicit a neutralizing immune response?

  • Ground Truth Answers: >500 Da>500 Da>500 Da

  • Prediction:

What kind of amino acids are overrepresented in epitope regions?

  • Ground Truth Answers: hydrophilic amino acidshydrophilichydrophilic amino acids

  • Prediction:

What is the study of proteins involved in immune response known as?

  • Ground Truth Answers: ImmunoproteomicsImmunoproteomicsImmunoproteomics

  • Prediction:

There is a public database of epitopes for pathogens known to be recognizable by what cells?

  • Ground Truth Answers: B cellsBB cells

  • Prediction:

What is the field of studying immunogenicity through bioinformatics known as?

  • Ground Truth Answers: immunoinformaticsimmunoinformaticsimmunoinformatics

  • Prediction:

What kind of immune response do smaller drugs provoke?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What does the neutralizing immune response mean for drugs based on smaller peptides and proteins?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is not a way that is used to predict the immunogenicity of peptides and proteins?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is underrepresented in epitope regions?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What is the study of small sets of proteins?

  • Ground Truth Answers: <No Answer>

  • Prediction:

In addition to the negative consequences of sleep deprivation, sleep and the intertwined circadian system have been shown to have strong regulatory effects on immunological functions affecting both the innate and the adaptive immunity. First, during the early slow-wave-sleep stage, a sudden drop in blood levels of cortisol, epinephrine, and norepinephrine induce increased blood levels of the hormones leptin, pituitary growth hormone, and prolactin. These signals induce a pro-inflammatory state through the production of the pro-inflammatory cytokines interleukin-1, interleukin-12, TNF-alpha and IFN-gamma. These cytokines then stimulate immune functions such as immune cells activation, proliferation, and differentiation. It is during this time that undifferentiated, or less differentiated, like naïve and central memory T cells, peak (i.e. during a time of a slowly evolving adaptive immune response). In addition to these effects, the milieu of hormones produced at this time (leptin, pituitary growth hormone, and prolactin) support the interactions between APCs and T-cells, a shift of the Th1/Th2 cytokine balance towards one that supports Th1, an increase in overall Th cell proliferation, and naïve T cell migration to lymph nodes. This milieu is also thought to support the formation of long-lasting immune memory through the initiation of Th1 immune responses.

Drop in the blood levels of cortisol and epinephrine results in increase levels of what hormones?

  • Ground Truth Answers: leptin, pituitary growth hormone, and prolactinleptin, pituitary growth hormone, and prolactinleptin

  • Prediction:

Hormones released during sleep support the interaction of T-cells and what species?

  • Ground Truth Answers: APCsAPCsAPCs

  • Prediction:

Sleep hormones shift the cytokine balance to which cytokine?

  • Ground Truth Answers: Th1one that supports Th1

  • Prediction:

Sleep hormone release supports formation of immune memory by initiating what immune response?

  • Ground Truth Answers: Th1 immune responsesTh1Th1 immune responses

  • Prediction:

What does sleep have no effect on?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What rises during early slow-wave-sleep stage?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What slows down immune functions during sleep?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What hormones are produced mostly when awake?

  • Ground Truth Answers: <No Answer>

  • Prediction:

What do hormones produced during this time stop from interacting?

  • Ground Truth Answers: <No Answer>

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Pathogens can rapidly evolve and adapt, and thereby avoid detection and neutralization by the immune system; however, multiple defense mechanisms have also evolved to recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess a rudimentary immune system, in the form of enzymes that protect against bacteriophage infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants and invertebrates. These mechanisms include phagocytosis, antimicrobial peptides called defensins, and the complement system. Jawed vertebrates, including humans, have even more sophisticated defense mechanisms, including the ability to adapt over time to recognize specific pathogens more efficiently. Adaptive (or acquired) immunity creates immunological memory after an initial response to a specific pathogen, leading to an enhanced response to subsequent encounters with that same pathogen. This process of acquired immunity is the basis of vaccination.

The immune systems of bacteria have enzymes that protect against infection by what kind of cells?

  • Ground Truth Answers: bacteriophagebacteriophagebacteriophage infections

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What are antimicrobial peptides that evolved as immune defense in eukaryotes called?

  • Ground Truth Answers: defensinsdefensinsdefensins

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The idea of acquired immunity in jawed vertebrates is the basis of what medical treatment?

  • Ground Truth Answers: vaccinationvaccinationvaccination

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What is the ability to recognize and adapt to new specific pathogens called?

  • Ground Truth Answers: Adaptive (or acquired) immunityAdaptive (or acquired) immunityAdaptive (or acquired) immunity

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What is known for adapting and evolving slowly?

  • Ground Truth Answers: <No Answer>

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What do simple unicellular organisms lack?

  • Ground Truth Answers: <No Answer>

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What is an example of a less sophisticated defense mechanism that jawed vertebrates have?

  • Ground Truth Answers: <No Answer>

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What creates immunological memory before the initial responds to a pathogen?

  • Ground Truth Answers: <No Answer>

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What medical treatment is completely different from acquired immunity?

  • Ground Truth Answers: <No Answer>

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In humans, this response is activated by complement binding to antibodies that have attached to these microbes or the binding of complement proteins to carbohydrates on the surfaces of microbes. This recognition signal triggers a rapid killing response. The speed of the response is a result of signal amplification that occurs following sequential proteolytic activation of complement molecules, which are also proteases. After complement proteins initially bind to the microbe, they activate their protease activity, which in turn activates other complement proteases, and so on. This produces a catalytic cascade that amplifies the initial signal by controlled positive feedback. The cascade results in the production of peptides that attract immune cells, increase vascular permeability, and opsonize (coat) the surface of a pathogen, marking it for destruction. This deposition of complement can also kill cells directly by disrupting their plasma membrane.

Complement proteins bind to what kind of molecules on the surface of microbes in order to elicit an immune response?

  • Ground Truth Answers: carbohydratescarbohydratescarbohydrates

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The speed of the killing response of the human immune system is a product of what process?

  • Ground Truth Answers: signal amplificationsignal amplificationsignal amplification

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What type of cascade results when complement proteins bind to microbes and activate their protease activity?

  • Ground Truth Answers: catalytic cascadecatalyticcatalytic

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How can the deposition of compliment kill invader cells directly?

  • Ground Truth Answers: disrupting their plasma membranedisrupting their plasma membranedisrupting their plasma membrane.

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What is this kind of response activated by plants?

  • Ground Truth Answers: <No Answer>

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What triggers a slow killing response?

  • Ground Truth Answers: <No Answer>

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What has nothing to do with the speed of the response?

  • Ground Truth Answers: <No Answer>

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What do complement proteins activate before they bind to the microbe?

  • Ground Truth Answers: <No Answer>

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What repels immune cells?

  • Ground Truth Answers: <No Answer>

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