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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Which of the following is least likely to be present and assist at a birth?
a. a doula b. an obstetrician c. a certified nurse-midwife d. a pediatrician
Suppose you visit a child development laboratory and observe a researcher working with an 8-month-old baby. The baby is sitting on top of a piece of Plexiglas, which rests partly over a table top and then extends out over the end of the table
The apparatus being used in this experiment is typically called a: a. visual cliff b. binocular challenge c. visually guided grid d. perceptual challenge map