Density. Density is the measurement of how much matter is in a substance
The OECD found that the responsiveness of housing supply to demand in the UK was the weakest among developed countries, due in large part to green belt policies. The green belt concept was first introduced for London in 1938 before the 1947 Town and Country Planning Act enabled local authorities to designate the status themselves. The policy was introduced to contain urban sprawl following huge post-war housing developments, and expanded greatly between 1951 and 1964. Since 1979, the green belt has doubled to cover 13 per cent of land in England (while only 2.3 per cent is covered by buildings).
The correct answer is antigens and epitope.
An antigen is a substance which triggers an immune response in an organism. This can be either a foreign substance, such as a pathogen, or a specific part of the host organism (in this case this is an autoimmune response). The presence of an antigen activates a specific part of the immune system, called antibody. Each antigen has a specific antibody, which is tailored by the immune system accordingly. More specifically, the antibody has a specific structure, called paratope, which is complementary and binds like a key to a specific structure of the antigen, called epitope.
Decomposers don't obtain energy, they release it into the environment.
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