Larsen's Human Embryology
Gary C. Schoenwolf, Steven B. Bleyl, Philip R. Brauer, and Philippa H. Francis-West
6th Edition
,Table of Contents
Introduction 1
Chapter 01 Gametogenesis, Fertilization, and First Week 3
Chapter 02 Second Week-Becoming Bilaminar and Fully Implanting 6
Chapter 03 Third Week-Becoming Trilaminar and Establishing Body Axes 8
Chapter 04 Fourth Week-Forming the Embryo 11
Chapter 05 Principles and Mechanisms of Morphogenesis and Dysmorphogenesis 14
Chapter 06 Fetal Development and the Fetus as a Patient 17
Chapter 07 Development of the Skin and Its Derivatives 20
Chapter 08 Development of the Musculoskeletal System 25
Chapter 09 Development of the Central Nervous System 30
Chapter 10 Development of the Peripheral Nervous System 34
Chapter 11 Development of the Respiratory System and Body Cavities 36
Chapter 12 Development of the Heart 39
Chapter 13 Development of the Vasculature 42
Chapter 14 Development of the Gastrointestinal Tract 45
Chapter 15 Development of the Urinary System 48
Chapter 16 Development of the Reproductive System 50
Chapter 17 Development of the Pharyngeal Apparatus and Face 52
Chapter 18 Development of the Ears 60
Chapter 19 Development of the Eyes 63
Chapter 20 Development of the Limbs 66
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
Schoenwolf: Larsen's Human Embryology, 6th Edition
Introduction
Test Bank
MULTIPLE CHOICE
1. Which phase of embryogenesis is characterized by extensive cell rearrangements that result in
formation of a multilayered embryo?
A. Organogenesis
B. Cleavage
C. Oogenesis
D. Spermatogenesis
E. Fertilization
F. Gastrulation
ANS: F
2. Which developmental signaling pathway is frequently mutated in patients with colon cancer?
A. FGF
B. WNT
C. SHH
D. BMP
E. PDGF
ANS: B
3. The period of the fetus occurs during which weeks postfertilization?
A. 1–4
B. 1–8
C. 1–12
D. 5–38
E. 9–38
F. 13–38
ANS: E
4. A child exhibiting early symptoms of progeria undergoes genetic testing. A gene coding for
which protein is likely to be mutated?
A. Laminin
B. Fibronectin
C. Collagen
D. Lamin-A
E. Insulin
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
Test Bank 2
ANS: D
5. A fetus is examined in utero by ultrasound, and a defect of its ventral body wall is noted. The
location of the defect corresponds to which surface of the adult?
A. Superior
B. Anterior
C. Medial
D. Posterior
E. Lateral
F. Inferior
ANS: B
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
Schoenwolf: Larsen's Human Embryology, 6th 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
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
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)
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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
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
Schoenwolf: Larsen's Human Embryology, 6th Edition
Chapter 2: Second Week: Becoming Bilaminar and Fully Implanting
Test Bank
MULTIPLE CHOICE
1. A young child is diagnosed with Angelman syndrome, a syndrome in which a deletion occurs
in a portion of the long arm of chromosome 15. Both Angelman syndrome and another
syndrome involve the same deletion, but the two syndromes differ depending on whether the
defect was inherited from the mother or father. What is the related syndrome?
A. Prader-Willi syndrome
B. Down syndrome
C. Treacher Collins syndrome
D. Branchio-oto-renal syndrome
E. CHARGE syndrome
ANS: A
2. A researcher inactivates the Sox17 gene in an animal model. As a result of this, one of the
primary germ layers fails to form. What germ layer is most likely to be affected?
A. Ectoderm
B. Somatic mesoderm
C. Splanchnic mesoderm
D. Extraembryonic mesoderm
E. Endoderm
ANS: E
3. The early conceptus can spontaneously abort if it doesn’t implant into the uterine wall and
develop a uteroplacental circulation. Which vessels of the embryo directly contribute to this
essential circulation?
A. Dorsal aortae
B. Precardinal veins
C. Vitelline arteries and veins
D. Allantoic arteries and veins
E. Postcardinal veins
ANS: D
4. A 45-year-old woman who tests positive on a home pregnancy test is later diagnosed with a
complete hydatidiform mole. What is unusual about the chromosomes of complete moles?
A. All chromosomes are derived from the mother.
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
B. All chromosomes are derived from the father.
C. Roughly two-thirds of the chromosomes are derived from the mother.
D. 23 chromosomes are present.
E. 69 chromosomes are present.
ANS: B
5. X inactivation is an example of which process?
A. Imprinting
B. Meiosis
C. Mitosis
D. Dosage compensation
E. Oogenesis
ANS: D
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Test Bank - Larsen's Human Embryology, 6th Edition (Schoenwolf, 2022)
Schoenwolf: Larsen's Human Embryology, 6th Edition
Chapter 3: Third Week: Becoming Trilaminar and Establishing Body Axes
Test Bank
MULTIPLE CHOICE
1. A researcher inactivates Lefty1, a gene expressed in the anterior visceral endoderm of the
mouse. What effect would inactivation of this gene have on the gastrula-stage embryo?
A. The epiblast becomes abnormally thickened throughout its cranial-caudal extent.
B. The primitive streak fails to form.
C. The endoderm fails to form.
D. The neural plate fails to form.
E. Extra primitive streaks form.
ANS: E
2. A boy is admitted to the hospital for an emergency appendectomy. During surgery it is noted
that the inflamed appendix is located on the left side, rather than the right side, and that the
patient has situs inversus viscerum totalis. Mutations in which gene are known to cause this
condition in animal models?
A. Pitx2
B. Bmp4
C. Hoxd13
D. Chordin
E. Tbx3
ANS: A
3. A man with recurrent respiratory infections and infertility is diagnosed with Kartagener
syndrome. Mutations in the gene encoding which protein cause this syndrome?
A. Dynein
B. Surfactant
C. FGF8
D. BMP2
E. Insulin
ANS: A
4. Rieger syndrome, which affects development of both the teeth and eyes, results from
haploinsufficiency in which gene in humans?
A. NODAL
B. PITX2
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