Chorionic villi contain
a. germ cells.
b. lymphatic vessels.
c. endometrial cells.
d. blood vessels.
e. the allantois.
D
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The gene pool of the next generation is derived from
A. all individuals of a population. B. only the female members of a population. C. those individuals of a population that reproduce and have viable offspring. D. individuals who are heterozygous for the genes in question. E. only the male members of a population.
If blood transports hormones throughout the body, how do they communicate with specific targets?
A. Axonal pathfinding mediates the delivery of hormones to their specific targets. B. Special gateway valves in the blood vessels direct hormones to their target tissues. C. Only target tissues have receptors that allow them to receive the signal. D. Special carrier proteins "walk" along microtubule tracts to deliver the hormones to their targets.
Altruistic behaviors between closely related animals
A. increase the inclusive fitness of the altruist. B. increase the life-time reproductive success of the altruist. C. reduce fighting between species. D. force individuals to cooperate with one another and thereby increase mating and population growth.
The transfer of specific molecules through cell membranes is an important factor in the process of
a. cytoplasmic flow b. mitotic division c. homeostatsis d. nuclear transfer