3.2 True/False Questions
1) Spina bifida results when the neural tube fails to close in the head.
2) The fetal period is the longer and later of the prenatal growth periods.
3) The inner cell mass will form the embryo, and the trophoblast will form the placenta.
4) The outer membrane of the amniotic sac is called the amnion.
5) The epiblast gives rise to the three primary germ layers.
6) The developing embryo, about 72 hours after fertilization, is called the zygote.
7) During the blastocyst stage, there are three cell layers evident.
8) It is easy to remember that in humans, 3 weeks after fertilization, there are three germ layers.
9) The three primary germ layers are the endoderm, myotome, and exoderm.
10) The yolk sac, formed from the hypoblast, has little yolk in the human embryo.
11) Premature birth is one that occurs 38 weeks after conception.
12) Endoderm forms many glands, such as those associated with the gastrointestinal tract.
13) The embryonic notochord gives rise to part of the intervertebral discs in the adult human.
14) Identical twins arise from the splitting of a three-layered embryo.
15) The ability of one group of cells to influence development of neighboring cells is called gastrulation.