Test Bank for Human Embryology and Developmental Biology, 6th Edition

Multiple Choice 1. Which component(s) of the cleaving embryo give(s) rise to tissues of the embryo itself? A. Corona radiata B. Trophoblast C. Zona pellucida D. Inner cell mass E. All of the above ANS: D 2. What is the correct cell lineage leading to the formation of the syncytiotrophoblast? A. Blastomere – inner cell mass – hypoblast – trophoblast – syncytiotrophoblast B. Inner cell mass – epiblast – cytotrophoblast – syncytiotrophoblast C. Blastomere – trophoblast – cytotrophoblast – syncytiotrophoblast D. Blastomere – inner cell mass – epiblast – trophoblast – syncytiotrophoblast E. Blastomere – epiblast – trophoblast – syncytiotrophoblast ANS: C 3. What is the most common condition associated with spontaneously aborted embryos? A. Maternal imprinting B. Lithopedion C. Ectopic pregnancy D. Chromosomal abnormalities E. Lack of X-chromosome inactivation ANS: D 4. Which tissue from the implanting embryo directly interfaces with the endometrial connective tissue? A. Inner cell mass B. Corona radiata C. Extraembryonic mesoderm D. Epiblast E. Syncytiotrophoblast ANS: E Copyright © 2014 by Saunders, an imprint of Elsevier Inc. Test Bank 3-2 5. Cells of which of the following are totipotent (can form any part of the embryonic body)? A. Inner cell mass B. Cytotrophoblast C. Amniotic ectoderm D. Extraembryonic mesoderm E. Yolk sac endoderm ANS: A 6. Which of the following is not a function of the zona pellucida? A. Preventing premature implantation B. Containing specific sperm receptors C. Keeping blastomeres of the embryo and its surrounding environment D. Serving as a filter between the embryo and its surrounding environment E. Aiding in the penetration of the endometrial epithelium ANS: E 7. Which of the following conditions results from inappropriate paternal imprinting? A. Conjoined twins B. Parasitic twin C. Hydatidiform mole D. Tetraparental mouse E. Fraternal twins ANS: C 8. A tubal pregnancy can result from: A. Pelvic inflammatory disease B. Scarring from a surgical procedure to a uterine tube C. An anatomical malformation of a uterine tube D. All of the above E. None of the above ANS: D 9. All of the following structures arise from the inner cell mass except: A. Epiblast B. Hypoblast C. Cytotrophoblast D. Parietal endoderm ANS: C Copyright © 2014 by Saunders, an imprint of Elsevier Inc. Test Bank 3-3 10. When the cleaving embryo implants in the uterine lining, which tissue makes direct contact with the maternal tissues? A. Inner cell mass B. Zona pellucida C. Hypoblast D. Extraembryonic mesoderm E. None of the above ANS: E 11. Identical twinning is made possible by what embryonic process? A. Induction B. Paternal imprinting C. X-chromosome inactivation D. Regulation E. Maternal imprinting ANS: D 12. In the construction of a tetraparental mouse, what property of the cleaving embryo allows the formation of a single mouse from two separate embryos? A. Induction B. Bateson’s rule C. Regulation D. Differentiation E. Restriction ANS: C 13. In early development, X inactivation first occurs in what tissue? A. Inner cell mass B. Primitive endoderm C. Notochord D. Hensen’s node E. Trophectoderm ANS: E Copyright © 2014 by Saunders, an imprint of Elsevier Inc. Test Bank 3-4 14. The fixation of the left-right asymmetry is initiated by the unequal distribution of molecules at the ____________. A. Prechordal plate B. Neural plate C. Primitive node D. Notochord E. None of the above ANS: C 15. The most common site for an ectopic pregnancy is the ________________. A. Uterus B. Cervix C. Abdominal cavity D. Uterine tube E. Ovary ANS: D 16. Which of the following is due to faulty parental imprinting? A. Ectopic pregnancy B. Placenta previa C. Hydatidiform mole D. Conjoined twins E. Situs inversus ANS: C 17. Embryonic stem cells are derived from the _______________. A. Corona radiata B. Inner cell mass C. Cytotrophoblast D. Syncytiotrophoblast E. None of the above ANS: B 18. Successful implantation depends on: A. Dissolution of the zona pellucida B. Production of syncytiotrophoblast C. Cell adhesion D. All of the above E. None of the above ANS: D Copyright © 2014 by Saunders, an imprint of Elsevier Inc.