The placental blood vessels
A) manufacture hormones that slow the growth of the embryo, preventing it from outgrowing the uterus.
B) allow for the exchange of wastes and nutrients but keep the maternal and fetal circulations separate.
C) draw oxygen from the fetal blood and pass it to the mother.
D) mix maternal blood and fetal blood.
E) prevent all microbes and toxins from crossing from mother to child.
B
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Answer the following statement true (T) or false (F)
Signaling molecules act locally or regionally to ________
a. all of the choices b. influence gene expression only c. regulate growth, development, and reproduction only d. adjust metabolism only
What did Mendel choose to study the inherited traits of pea plants?
a. Pea plants were known to have relatively few, easily manipulated chromosomes compared to other available organisms. b. Pea plants were the only organisms he could reasonably breed in his facilities at the monastery where he lived and worked. c. Peas were a profitable agricultural product for the monastery, allowing his research to be self-funded indefinitely. d. The pea plants had discontinuously variable traits, which allowed underlying probabilities of inheritance to be inferred.
Sitting at the top of a slide, a child has ________ energy; sliding down, she is using ________ energy
Fill in the blank(s) with correct word