Problem: Agrobacterium tumefaciens, a soil rhizosphere bacterium, can attach to plant cells and infect them with a callus-inducing Ti plasmid by horizontal gene transfer, causing a callus infection called crown gall disease. Schell and Van Montagu (1977) hypothesised that the Ti plasmid could be a natural vector for introducing the Nif gene responsible for nitrogen fixation in the root nodules of legumes and other plant species. Today, genetic modification of the Ti plasmid is one of the main techniques for introduction of transgenes to plants and the creation of genetically modified crops.
How can a bacteria in the soil affect a plant?
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Answer: can attach to plant cells


Problem: In agriculture, the increased usage of sheep with long-fibred wool allowed a stronger thread to be spun. In addition, the spinning wheel replaced the traditional distaff for spinning wool, tripling production.[AI] A less technological refinement that still greatly affected daily life was the use of buttons as closures for garments, which allowed for better fitting without having to lace clothing on the wearer. Windmills were refined with the creation of the tower mill, allowing the upper part of the windmill to be spun around to face the direction from which the wind was blowing. The blast furnace appeared around 1350 in Sweden, increasing the quantity of iron produced and improving its quality. The first patent law in 1447 in Venice protected the rights of inventors to their inventions.
In what country did the blast furnace first appear?
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Answer: Sweden


Problem: The boroughs are composed by hundreds of colonias or neighborhoods, which have no jurisdictional autonomy or representation. The Historic Center is the oldest part of the city (along with some other, formerly separate colonial towns such as Coyoacán and San Ángel), some of the buildings dating back to the 16th century. Other well-known central neighborhoods include Condesa, known for its Art Deco architecture and its restaurant scene; Colonia Roma, a beaux arts neighborhood and artistic and culinary hot-spot, the Zona Rosa, formerly the center of nightlife and restaurants, now reborn as the center of the LGBT and Korean-Mexican communities; and Tepito and La Lagunilla, known for their local working-class foklore and large flea markets. Santa María la Ribera and San Rafael are the latest neighborhoods of magnificent Porfiriato architecture seeing the first signs of gentrification.
What is the oldest part of the city?
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Answer:
The Historic Center