The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.
What is encoded on a chromosome?
thousands of genes

Port of Nanjing is the largest inland port in China, with annual cargo tonnage reached 191,970,000 t in 2012. The port area is 98 kilometres (61 mi) in length and has 64 berths including 16 berths for ships with a tonnage of more than 10,000. Nanjing is also the biggest container port along the Yangtze River; in March 2004, the one million container-capacity base, Longtan Containers Port Area opened, further consolidating Nanjing as the leading port in the region. As of 2010, it operated six public ports and three industrial ports.
What is the largest inland port for China?
Port of Nanjing

The tram system that now criss-crosses the historic city centre complements walking and biking in it. The centre has been transformed into a pedestrian priority zone that enables and invites walking and biking by making these active modes of transport comfortable, safe and enjoyable. These attributes are accomplished by applying the principle of "filtered permeability" to the existing irregular network of streets. It means that the network adaptations favour active transportation and, selectively, "filter out" the car by reducing the number of streets that run through the centre. While certain streets are discontinuous for cars, they connect to a network of pedestrian and bike paths which permeate the entire centre. In addition, these paths go through public squares and open spaces increasing the enjoyment of the trip. This logic of filtering a mode of transport is fully expressed in a comprehensive model for laying out neighbourhoods and districts – the Fused Grid.
What is the layout of the neighbourhoods called?
Fused Grid