Deck 10: Development of the Central Nervous System

Question 1

Weaver mice provide insight into mechanisms of cerebellar development.What gene is mutated in these mice?

A) Girk2
B) Phosphatidylinositol transfer protein alpha
C) Calcium channel alpha(1A) subunit
D) Zic2
E) Ephrin-A2

Answer 1

A

Question 2

A child is diagnosed with Kallmann syndrome.Genetic evaluation revealed a mutation in the patient of the KAL1 gene.What does this gene encode?

A) Beta-catenin
B) FGFR1
C) Anosmin-1
D) Platelet-activating factor acetyhydrolase
E) Doublecortin

Answer 2

C

Question 3

A researcher interested in patterning of the early neural tube identifies a new secreted factor expressed in the floor plate.Assuming that the newly identified factor plays a role in patterning,which axis of the developing neural tube would you expect to be perturbed if this factor is inactivated?

A) Cranial-caudal
B) Dorsal-ventral
C) Medial-lateral
D) Right-left

Answer 3

B

Question 4

A researcher knocks out Ephrin-B2 in the developing visual system.What effect will this have on retinal ganglion cell (RGC)axon projection?

A) There will be no effect.
B) Half of the RGC axons will project ipsilaterally.
C) All of the RGC axons will project ipsilaterally.
D) All of the RBC axons will project contralaterally.

Question 5

An investigator injects a cell lineage marker into the developing ventricular zone of the ganglionic eminence of the developing forebrain.Cells in which region of the neonatal brain will be labeled?

A) Basal ganglia
B) Superior colliculus
C) Inferior colliculus
D) Neocortex
E) Brain stem

Question 6

A 45-year-old man develops Bell's palsy in which function of the facial (VII)cranial nerve is compromised.What specific level of the central nervous system does the facial nerve connect to?

A) Telencephalon
B) Diencephalon
C) Mesencephalon
D) Metencephalon
E) Myelencephalon
F) Spinal cord

Question 7

A 4-year-old girl is diagnosed with cerebellar heterotopia.What developmental process likely went awry,accounting for heterotopia?

A) Cell proliferation
B) Cell death
C) Axonal pathfinding
D) Cell migration
E) Cell differentiation

Question 8

A 3-year-old boy with spina bifida develops hydrocephalus.What is the likely cause of this?

A) Blockage of the subarachnoid space
B) Enlargement of the choroid plexus
C) Constriction of the foramen magnum
D) Blockage of the median or lateral apertures
E) Degeneration of the choroid plexus

Question 9

A researcher interested in patterning of the early neural tube identifies a new secreted factor expressed in the isthmus signaling center.Assuming that the newly identified factor plays a role in patterning,which axis of the developing neural tube would you expect to be perturbed if this factor is inactivated?

A) Cranial-caudal
B) Dorsal-ventral
C) Medial-lateral
D) Right-left

Question 10

A 13-year-old girl develops a tumor of the anterior pituitary gland.What is the embryologic origin of the anterior pituitary gland?

A) Rathke's pouch
B) Infundibulum of diencephalon
C) Neural crest cells
D) Pharyngeal pouch 1
E) Laryngotracheal groove

Question 11

A researcher knocks out the Soho gene in the rudiment of the developing mouse eye.What aspect of eye development will be affected?

A) Dorsal-ventral axis of the neural retina
B) Cranial-caudal axis of the neural retina
C) Nasal-temporal axis of the neural retina
D) Induction of the lens
E) Induction of the cornea

Question 12

A 20-year-old woman suffers a stroke after a drug overdose that causes localized damage to the brain stem special somatic afferent column on one side.Sensation from which structure(s)will be compromised?

A) Skin
B) Taste buds
C) Nonstriated muscle
D) Inner ear
E) Somatic striated muscle

Question 13

A surgeon operates on the lumbar nervous system to relieve intractable pain in a terminal cancer patient.What specific part of the nervous system would be cut?

A) Visceral root
B) Dorsal root
C) Ventral root
D) Spinal nerve
E) Basal plate of the spinal cord

Question 14

A researcher labels a small area of the neural tube at the future cerebellar level.It is later noted that cells in the deep cerebellar nuclei are labeled.What portion of the neural tube was labeled in this experiment?

A) Ventricular zone
B) Marginal zone
C) Mantle zone
D) External germinal layer
E) Internal germinal layer
F) Ependyma

Question 15

A researcher treats an early neural-tube-stage embryo with a 1-hour pulse of colchicine,which arrests proliferating cells in metaphase.Where will the arrested cells be found?

A) Throughout the marginal layer of the neural tube
B) Throughout the mantle layer of the neural tube
C) Throughout the ventricular layer of the neural tube
D) Only in the floor plate of the neural tube
E) Only in the roof plate of the neural tube