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T-helper cells are a kind of lymphocyte that are a key part of the adaptive immune system. The adaptive immune system is largely coordinated by T cells, of which there are several types, and B cells, the ...
Deoxygenated blood from the body drains into the right atrium of the heart through the superior and inferior vena cava blood vessels. The blood then travels from the right atrium, through the tricuspid va...
DNA is a universal code for all living beings known to man. There are four nucleotide bases in DNA and RNA, the combinations of these sequences are what determine the order and length of a polypeptide. Ev...
What is speciation?When a new and distinct species evolves from an ancestor speciesReproductively isolated from the ancestor/other species2. How does natural selection work?a. Population of individuals, w...
Nucleus- controls the activity of the cellMitochondria- site of aerobic respirationCytoplasm- site of biochemical reactions, including anaerobic respiration Cell membrane- Allows transport of materials in...
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