PRACTICE EXAM ANSWERS - AUTONOMIC NERVOUS SYSTEM, EMBRYOGENESIS
1. __B__ The intercostal
nerve of the 7th intercostal space in the midaxillary line contains
A. preganglionic sympathetic
fibers.
B. somatic sensory fibers.
C. preganglionic parasympathetic
fibers.
D. postganglionic parasympathetic
fibers.
E. Both B and D.
2. __E__ Parasympathetic preganglionic
fibers are
A. myelinated.
B. found in the white ramus
communicans.
C. shorter than the parasympathetic
postganglionic fibers.
D. found in the ventral root
of S3 (sacral) spinal nerve.
E. Both A and D.
3. __B__ Postganglionic sympathetic
fibers from the pre-aortic ganglia
A. form named nerves (e.g.
splanchnic), which innervate abdominal viscera.
B. travel with branches of
the aorta to reach the abdominal viscera.
C. synapse on sympathetic
chain ganglia.
D. join the gray rami communicans
of lumbar spinal nerves.
E. None of the above.
4. __C__ The sympathetic trunk
A. contains postganglionic
fibers that ascend or descend to different spinal levels.
B. has chain ganglia only
at levels T1-L2.
C. is located paravertebrally,
from C1 to the coccyx.
D. is found within the posterior
mediastinum.
E. is located lateral to
the parietal pleura at upper thoracic levels.
5. __D__ Splanchnic nerves
A. synapse on sympathetic
chain ganglia.
B. contain preganglionic
fibers that synapse on mural ganglia
of the stomach.
C. hitch a ride on branches
of the aorta to reach organs.
D. contain preganglionic
sympathetic fibers.
E. Both B and C.
6. __E__ The dorsal root of
a spinal nerve
A. contains visceral and
somatic sensory fibers.
B. contains somatic motor
fibers that innervate intrinsic
back muscles.
C. joins the ventral root
to form a spinal nerve.
D. courses lateral to the
intervertebral foramen to form
the spinal nerve.
E. Both A and C.
7. __C__ Vagal fibers
A. are found in cranial nerve
9.
B. innervate the sweat glands
of the skin of the thorax.
C. synapse on mural ganglia
in the small intestine.
D. are postganglionic fibers.
E. are found in the white
ramus communicans.
8. __B__ The event which triggers
the completion of meiotic divisions
of the developing ovum is
A. ovulation
B. fertilization
C. rapid increase in estrogen
D. breakdown of zona pellucida
E. none of the above
9. __E__ Cleavage of the zygote
A. is initiated by fertilization.
B. results in an increase
in total volume of the incipient
embryo.
C. occurs within the zona
pellucida.
D. results in the direct
formation of the blastocyst.
E. Both A and C.
10. __B__ Neural crest ectoderm
gives rise to all of the following
EXCEPT
A. sensory neurons.
B. somatic motor neurons.
C. adrenal (suprarenal) medulla.
D. melanocytes of the skin.
E. sympathetic chain ganglia.
11. __D__ The amniotic cavity
develops
A. during week 1
B. within the inner cell
mass
C. in extraembryonic mesoderm
D. between the inner cell
mass and the trophoblast
E. none of the above
12. __B__ The allantois
A. forms the definitive medial
umbilical ligament.
B. is a diverticulum of the
hindgut (caudal yolk sac).
C. completely degenerates
postnatally.
D. is an outpouching of the
coelom into the connecting stalk.
E. is not found in the umbilical
cord at any time.
13. __E__ Which of the following
statements are TRUE in relation to
the anatomical "events" that result from head folding
of the embryonic disc?
A. The septum transversum
is now located rostral to the heart.
B. The heart is located dorsal
to the pericardial coelom.
C. Myoblasts from the paraxial
mesoderm of somites C3-C6 migrate
into the septum transversum.
D. The rostral part of the
yolk sac is incorporated into
the embryo to form the foregut.
E. Both B and D.
14. __E__ Which of the following
statements is TRUE in regards to gastrulation?
A. begins during week 4 of
development.
B. epiblast cells migrate
into the primitive groove to form
the neural tube.
C. primitive streak extends
caudally from the oropharyngeal
membrane to the primitive knot.
D. cloacal membrane contains
3 germ layers.
E. None of the above.
15. __C__ Intraembryonic somatic
mesoderm from the lateral plate forms
the
A. epidermis of the skin.
B. smooth muscle of the wall
of the esophagus.
C. pectoralis minor muscle.
D. intercostal muscles.
E. dermis of the skin.
16. __D__ Prior to birth, primary
oocytes
A. contain the haploid number
of chromosomes.
B. are surrounded by the
zona pellucida.
C. are found with the 1st
polar body within a follicle.
D. begin meiosis I but stopped
until 48 hours prior to ovulation.
E. Both C and D.
17. __A__ The chorionic cavity
(extra-embryonic coelom)
A. is lined by extra-embryonic
mesoderm.
B. is obliterated by the
expansion of the placenta.
C. is formed initially during
postnatal week 3.
D. is located between the
cytotrophoblast and syn-cytiotrophoblast.
E. None of the above.
18. __A__ The dermatome at the
nipple of the mammary gland is innervated
by
A. ventral ramus of T4 spinal
nerve.
B. ventral ramus of T5 spinal
nerve.
C. 3rd intercostal nerve.
D. postganglionic parasympathetic
fibers.
E. dorsal ramus of 4th intercostal
nerve.
PART II. MULTIPLE COMPLETION-
Under the initial statement of each
question are four statements that complete or pertain to it.
READ ALL statements very
CAREFULLY AND THEN CHOOSE THE APPROPRIATE
ANSWER.
CHOOSE:
A=1, 2, and 3
B= 1 and 3
C= 2 and 4
D= 4 only
E=all
1. __A__ The dorsal ramus of
spinal nerve L1 contains
1. cutaneous sensory fibers
from the back
2. postganglionic sympathetic
fibers
3. motor fibers to the intrinsic
back muscles
4. motor fibers to intercostal
muscles of the posterior
thoracic wall.
2. __B__ The sacral component
of the parasympathetic nervous system
1. has postganglionic fibers
which innervate structures derived
embryologically from the hindgut (e.g., rectum
).
2. has preganglionic neuronal
cell bodies located in the
intermediolateral cell column.
3. has preganglionic fibers
that enter the ventral ramus
of a sacral spinal nerve.
4. has preganglionic fibers
contained within white rami communicans
of sacral spinal nerves.
Part III. TRUE-FALSE: Fill
in the blank space on the computer answer
sheet for (A) if the statement is TRUE and for (B) if the
statement is FALSE.
1. __B__ Spinal nerve C7 exits
the spinal canal between the last cervical
and the first thoracic vertebrae.
2. __B__ The zona pellucida
doesn't break down until the blastula
has implanted into the endometrium of the uterus.
3. __B__ An intercostal nerve
can be composed of fibers from more
than one thoracic spinal nerve.
4. __A__ The notochord induces
the overlying ectoderm to transform
into the neural plate.
5. __A__ Lateral folding of
the embryo results in the formation of
lateral and ventral body walls during week 4. |
