MULTIPLE CHOICE 1. A child with a large sacrococcygeal teratoma is delivered by cesarean section. The teratoma likely arose from which type of cells? A. Neuroectodermal stem cells B. Neural crest cells C. Primitive streak cells D. Primordial germ cells E. Secondary oocyte cells ANS: D 2. A baby is diagnosed with Down syndrome shortly after birth. Which of the following events occurred abnormally during prenatal development? A. Anaphase of mitosis B. Metaphase of mitosis C. Telophase of mitosis D. Anaphase of meiosis E. Metaphase of spermatogenesis ANS: D 3. The birth control pill acts by blocking which process? A. Fertilization B. Ovulation C. Cleavage D. Capacitation E. Implantation ANS: B 4. RU-486 is an effective abortifacient. It acts by which mechanism? A. Blocking oogenesis B. Causing menstruation C. Blocking ovulation D. Causing polyspermy E. Blocking capacitation