Answer:
interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It is a 15.5–16 kDa protein[5] that regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible for immunity. IL-2 is part of the body's natural response to microbial infection, and in discriminating between foreign ("non-self") and "self". IL-2 mediates its effects by binding to IL-2 receptors, which are expressed by lymphocytes. The major sources of IL-2 are activated CD4+ T cells and activated CD8+ T cells
Explanation:
It increases because the higher you go in the food chain, the bigger the carnivores or consumers are.
Explanation:
Scientific laws and scientific theories are very similar.
They both discuss and observe phenomena that have already occurred and been evaluated.
The main difference between the two is that law defines nature and what it does conditionally, and the reaction of nature when these conditions encounter.
To sum it up, law discusses the behavior of something that transpires in many annotations.
A theory on the other hand discusses not the behavior, but the functions. The “why” factor so to speak.
Answer:
option D
Explanation:
more than half of global population growth between now and 2050 is expected to occur in Africa. Africa has the highest rate of population growth among major areas
B.............................................................................................................