Which statement about human prenatal development is true?
A) Exposure to drugs or radiation is most harmful during the third trimester.
B) By the end of the first month, the developing human is considered a fetus.
C) At 4 weeks gestation, most of the embryo's organ systems have formed.
D) Growth occurs most rapidly during the first trimester.
E) Internal organs such as the lungs are mature by the end of the second trimester.

Question

Quizplus · Accepted Answer

By 4 weeks gestation, the basic structures of most organ systems have begun to form, although they are not fully developed.

Which Statement About Human Prenatal Development Is True