Exam Review Flashcards
In-class exam review
Tendons of limb muscles arise from the lateral plate mesoderm. Limb muscles arise from which of the following sources?
A. Dorsal lip of the myotome
B. Ventral buds of myotomes
C. Ventrolateral dermomyotome
D. Paraxial somitomeres
C. Ventrolateral dermomyotome
Pre-muscles cells in the developing limb bud are derived from which of the following sources?
A. Lateral plate mesoderm
B. Somitic dermatomes
C. Somitic myotomes
D. Neural Crest
C. Somitic myotomes
Which of the following represents the principle function of the AER?
A. Stimulating outgrowth of the limb bud
B. Setting up the AP axis of the limb bud
C. Determining the specific characteristics of the ectodermal appendages of the limb
D. Determining the pattern of neural outgrowth of the limb
A. Stimulating outgrowth of the limb bud
If the limb disc of a salamander embryo is rotated 180 degrees, so that both AP and the DV axes are reversed, which of the following would be observed?
A. The resulting limb would be completely normal with no reversal of axes
B. The AP axis of the resulting limb would be reversed but not the DV axis
C. The DV axis of the resulting limb would be reversed but not the AP axis
D. Both the AP and the DV axes of the resulting limb would be reversed
B. The AP axis of the resulting limb would be reversed but not the DV axis
Numerous experiments have shown that retinoid acid is capable of inducing the formation of the posterior limb in vertebrates. Retinoid acid is not the actual morphogen but is capable of activating which of the following genes, which is thought to express the actual morphogen?
A. Sonic hedgehog
B. Wnt-7 gene
C. Pax-3 gene
D. Noggin Gene
A. Sonic hedgehog
Pattern formation along the proximodistal axis of the limb bud is primarily determined by which of the following?
A. Pax-a gene
B. Hox-d gene
C. Retinoid acid
D. Sonic Hedgehog
B. Hox-d gene
The presence of webbing between the toes of wading birds such as ducks and the presence of webbed fingers (syndactyly) is most likely associated with which of the following?
A. Overexpression of Noggin
B. Oligohydramnios
C. Reduced apoptotic activity
D. Amniocentesis
C. Reduced apoptotic activity
Which of the following experiments carried out on the salamander embryos illustrates that the developing limb is a highly regulative system?
A. Split a limb primordial into two halves and prevent them from fusing
B. Juxtapose two equivalent halves of a limb primordium
C. Remove part of a limb primordial
D. All the above
D. All the above
Which of the following factors functions as the initial initiator of future hindlimb development?
A. Hox-d
B. Tbx4
C. Shh
D. Gli3
B. Tbx4
In limb development, the attraction of the outgrowing nerves to peripheral organs seems to be unspecific to a very high degree. Connections between a nerve and the end organ can be made only if the two correspond to each other. These assumptions are based on which of the following experiments?
A. An eye was transplanted to the side of a salamander embryo after the forelimb rudiment was removed.
B. A salamander forelimb bud was removed and replaced by a hindlimb bud.
C. A salamander limb rudiment was translanted to the flank (side) of a host salamander.
D. An obstacle (i.e., piece of mica) was placed between the spinal cord and the region where the hindlimb rudiment was to develop in a salamander embryo.
A. An eye was transplanted to the side of a salamander embryo after the forelimb rudiment was removed.
During limb development, pre-muscle cells in the somite express c-met, which is the receptor for which of the following?
A. Pax-3
B. N-cadherin
C. Tcf-4
D. Scatter factor
D. Scatter factor
In the formation of limb joints, which of the following signal molecules is responsible for inhibiting BMP in the region of the future joint cavity?
A. Shh
B. Noggin
C. Wnt-1
D. Eng-1
B. Noggin
Which of the following occurs when an additional limb bud is transplanted into the immediate vicinity of the host forelimb of a salamander embryo?
A. Neither limb bud will be supplied by any branches of the brachial plexus.
B. The brachial nerves will develop branches running out to the additional limb and will supply it.
C. The transplanted limb bud will be supplied by local nerves that would normally supply flank muscles.
D. Local brachial plexus nerves deviate from the normal limb bud and supply only the transplanted limb bud.
B. The brachial nerves will develop branches running out to the additional limb and will supply it.
From exam review*
C. The transplanted limb bud will be supplied by local nerves that would normally supply flank muscles.
The formation of clubfoot (talipes equinovarus) is associated with which of the following?
A. A misplaced ZPA B. Defective cellular migration from somites C. Thalidomide D. Oligohydramnios E. A neural crest defect
D. Oligohydramnios
Which of the following is observed when the forelimb rudiment of a salamander embryo is removed so that the limb fails to develop?
A. The associated spinal ganglia increase to more than 150% of their normal size
B. Local nerves are not affected
C. The nerves of the brachial plexus remain smaller (thinner) than they would have been if the limb were still there
D. Nerves of the future brachial plexus undergo apoptosis
C. The nerves of the brachial plexus remain smaller (thinner) than they would have been if the limb were still there
Which of the following are NOT derived from neural crest cells?
A. Postganglionic autonomic neurons
B. Autonomic ganglia
C. Sensory neuron cell bodies
D. Motor neuron cell bodies
D. Motor neuron cell bodies
Which of these cell and tissue types arises from cranial, but not trunk, neural crest cells?
A. Sensory ganglia B. Adrenal medulla C. Melanocytes D. Schwann cells E. None of the above
E. None of the above
Which of the following is a poor sublate for migrating neural crest cells?
A. Laminin B. Chondroitin Sulfate C. Fibronectin D. Type IV vollagen E. Hyaluronic acid
B. Chondroitin Sulfate
Neural crest cells arise from which of the following?
A. Somite B. Dorsal non-neural ectoderm C. Neural plate D. Splanchnic mesoderm E. Yolk sac endoderm
C. Neural plate
A 65-month old infant exhibits congenital defects, including a cleft palate, deafness, ocular hypertelorism, and a white forelock but otherwise dark hair on his head. Which of the following represents the probable diagnosis?
A. CHARGE association B. Von Recklinghausen's disease C. Hirschsprung's disease D. Waardenburg's syndrome E. None of the above
D. Waardenburg’s syndrome
Which of the following is involved in the migration of neural crest cells from the neural tube?
A. Snail B. BMP-2 C. Mash-1 D. Norepinephrine E. Glial growth factor
A. Snail
Which is not a derivative of the neural crest?
A. Sensory neurons B. Motor neurons C. Schwann cells D. Adrenal medulla E. Dental pailla
B. Motor neurons
If trunk neural crest cells are transplanted into the cranial region, they can form all of the following types of cells except:
A. Pigment cell B. Schwann cells C. Sensory neurons D. Cartilage E. Autonomic neurons
D. Cartilage
Which of the following syndromes is characterized by reduced function of the thymus, thyroid, and parathyroid glands, cardiovascular defects, and abnormalities of the aortic arches and is the result of a defect in the neural crest supplying the third and fourth pharyngeal arches?
A. Neurofibromas
B. diGeorge syndrome
C. Waardenberg’s syndrome
D. CHARGE
B. diGeorge syndrome
Most neural crest cells originating from the areas of somites 1-3 will follow the circumpharyngeal path and will make up which of the following divisions?
A. Cardiac neural crest
B. Vagal neural crest
C. Sympathoadrenal neural crest
D. Spinal gangli neural crest
A. Cardiac neural crest
Which of the following conclusions concerning the choroid fissure is correct?
A. The optic nerve and the hyaloid artery both use the choroid fissure to reach the posterior chamber of the eye
B. Low concentrations of Shh are necessary to guide the axons of the ganglion cells along the choroid fissure to the retina
C. Failure of the choroid fissure to close results in the formation of cyclopia
D. The hyaloid artery uses the choroid fissure to reach the posterior chamber of the eye
D. The hyaloid artery uses the choroid fissure to reach the posterior chamber of the eye
Neural crest-derived cells constitute a significant component of which tissue of the eye?
A. Neural retina B. Lens C. Optic nerve D. Cornea E. None of the above
D. Cornea
What molecules plays a role in guidance of advancing retinal axons through the optic nerve?
A. Pax-2 B. FGF-3 C. BMP-4 D. Pax-6 E. BMP-7
A. Pax-2
Surface ectoderm is induced to become corneal epithelium by an inductive event originating in which of the following?
A. Optic cup B. Chordamesoderm C. Optic Vesicle D. Lens vesicle E. Neural retina
D. Lens vesicle
Which fo the following is caused by failure of the choroid fissure to close during the sixth week of pregnancy?
A. Anopthalmos
B. Microphthalamos
C. Cyclopia
D. Colobomo
D. Colobomo