Schoenwolf et al.: Larsen's Human Embryology, 5th Edition

Chapter 1: Gametogenesis, Fertilization, and First Week

Test Bank

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

ANS: B

5.	A 36-year-old woman is unable to conceive a child because both her oviducts were severely scarred by pelvic inflammatory disease resulting from gonorrhea. Which type of assisted reproductive technology could be used to help her conceive?
A.	Gamete intrafallopian transfer (GIFT)
B.	Zygote intrafallopian transfer (ZIFT)
C.	In vitro fertilization (IVF) and embryo transfer

ANS: C

6.	A researcher knocks out expression of the POU domain transcription factor Oct4 in the early epiblast of a mouse embryo. Which cell type would you expect to be affected?
A.	Neural crest cells
B.	Neural plate cells
C.	Mesodermal cells
D.	Primordial germ cells
E.	Endodermal cells

ANS: D

7.	Formation of haploid spermatozoa occurs during which developmental event?
A.	Spermiation
B.	Capacitation
C.	Spermatogenesis
D.	Spermiogenesis
E.	Fertilization

ANS: C

8.	Increase in the levels of which hormone prevents menstruation during a cycle in which fertilization occurs?
A.	LH
B.	FSH
C.	GnRH
D.	hCG
E.	Estrogen

ANS: D

9.	A newborn girl is suspected of having Turner syndrome. Which diagnostic procedure would be used to determine if this is indeed the case?
A.	Karotyping
B.	Spectral karotyping (SKY)
C.	Comparative genomic hybridization (CGH)
D.	Fluorescent in situ hybridization (FISH)

ANS: A

10.	A researcher establishes mouse spermatozoa lacking one of the following two sperm-specific proteins: Izumo and CD9. Which developmental events will be perturbed in the absence of either of these proteins?
A.	Spermatogenesis
B.	Capacitation
C.	Binding of spermatozoa to the zona pellucida
D.	Fusion of the egg and spermatozoa membranes
E.	Spermiogenesis

ANS: D