Chapter 27: Human Development and Heredity Herlihy: The Human Body in Health and Illness, 6th Edition

Chapter 27: Human Development and Heredity Herlihy: The Human Body in Health and Illness, 6th Edition MULTIPLE CHOICE 1. Which structure is commonly called the bag of waters (it breaks prior to delivery and often signals the onset of labor)? a. Primary germ layers b. Morula c. Amniotic sac d. Blastocyst ANS: C 2. What term describes the ectoderm, mesoderm, and endoderm? a. Inner cell mass b. Extraembryonic membranes c. Primary germ layers d. Blastomeres ANS: C 3. What is the outer extraembryonic membrane that forms finger-like projections called villi and helps form the placenta? a. Amnion b. Chorion c. Umbilicus d. Trophoblast ANS: B 4. Which of the following is a disclike structure where the fetal and maternal circulations meet (baby eats, excretes, and breathes at this site)? a. Umbilicus b. Placenta c. Primary germ layers d. Zygote ANS: B 5. Which of the following develops first? a. Morula b. Trophoblast c. Blastomere d. Zygote ANS: D