The yolk sac __________
A) forms during the third trimester of pregnancy
B) is the outer ring of cells that surrounds the blastocyst
C) produces blood cells until the organs are mature enough to take over this function
D) contains one large vein that delivers blood loaded with nutrients and two arteries that remove waste
Answer: C
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The most common reaction to a chronic illness is:
a. denial c. bargaining. b. depression d. fear
A mental block to problem solving that is due to excessive self-criticism or involves an inability to tolerate ambiguity is called
a. perceptual consolidation. b. an emotional barrier. c. a conceptual block. d. functional fixedness.
For girls, the mid-point of puberty is frequently assessed via her report of:
A) menarche, or her first period. B) hormonal and mood changes. C) breast development. D) pubic hair development.
What is the correct denominator for the repeated-measures F-ratio?
A) ?MSerror B) ?MSwithin C) ?MSbetween subjects D) ?MSbetween treatments