The yolk sac
A) produces blood cells until the developing liver, spleen, and bone marrow are mature enough to take over this function.
B) forms a membrane that encloses the developing organism.
C) helps keep the temperature of the prenatal world constant.
D) provides a cushion against any jolts caused by the mother's movement.
A
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Cells found in the nervous system that insulate, nourish, and remove waste products from neurons are known as
a. neurotransmitters. b. myelin sheaths. c. glia. d. synapses.
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What will be an ideal response?
A(n) __________ situation is one in which a person is isolated or cut off from alternative viewpoints and is given strict rewards and punishments from leaders
a. isolated b. persuasive c. comparative d. total
The belief that explanations of phenomena and events should remain simple until these simple
explanations are no longer valid is known as the A) experimental design B) William's Principle C) Principle of Parsimony D) Principle of Science