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The answer is apex and base. To simplify, the apex of the heart rests on the diaphragm and from its base, the great vessels emerge. In addition, blood vessels that are nearer to the pumping heart and must enlarge to endure pressure variations are named elastic arteries and foramen ovale permits blood to pass from the right to the left atrium, therefore avoiding to pass the fetal lungs.
<span>Cytotoxic t-cell subpopulations are specialized to combat intracellular pathogens, whereas helper t-cell subpopulations are specialized to combat extracellular pathogens.
</span>Cytotoxic t-cell are CD8+ cells. Cytotoxic t-cell uses granzymes to <span>kill </span><span>intracellular bacteria, that lives in the cytosol such as viruses. They identify the pathogen forgein peptids that are bounded to MHC-I on the cell surface.
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cd4+ T helper (Th) cells include Th1, Th2, and Th17 cells. They contribute to aliergic reactions and fighting extracellular parasites.
Answer:
FF | FA
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FA | AA
Explanation:
F= free ear lobed male A= female with attached earlobes
FF | FA
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FA | AA