Chapter 4 : Development of the Nervous Systems (4)

Question 1

1. The neural retina is derived from the (A) alar plate (B) choroid (C) neural crest (D) neural tube (E) telencephalic vesicle wall

Answer 1

1–D. The retina is derived from the neural tube, which gives rise to the entire CNS.

Question 2

2. At birth, the conus medullaris is found at which vertebral level? (A) VT12 (B) VL1 (C) VL3 (D) VS1

Answer 2

2–C. At birth, the conus medullaris extends to VL3, and in the adult it extends to the VL1–VL2 interspace. At 8 weeks, the spinal cord extends the entire length of the vertebral canal.

Question 3

3. Caudal herniation of the cerebellar tonsils and medulla through the foramen magnum is called (A) Dandy-Walker syndrome (B) Down syndrome (C) Arnold-Chiari syndrome (D) cranium bifidum (E) myeloschisis

Answer 3

3–C. Arnold-Chiari syndrome is a cerebello medullary malformation in which the inferior vermis and medulla herniate through the foramen magnum, resulting in communicating hydro cephalus.Arnold-Chiari syndrome is frequently associated with spina bifida.

Question 4

4. A newborn has multiple congenital defects due to dysgenesis of the neural crest. Which of the following cells is most likely to be spared? (A) Dorsal root ganglion cells (B) Geniculate ganglion cells (C) Melanocytes (D) Motor neurons (E) Parafollicular cells

Answer 4

4–D. Motor neurons develop from the neural tube, more specifically from the basal plate. The other options are derivatives of the neural crest.

Question 5

Questions 5 to 9
Match the statements in items 5 to 9 with the appropriate lettered structure shown in the figure.

5. Is derived from the telencephalon

Answer 5

5–C. The corticospinal tract (pyramid) has its origin in the neocortex of the telencephalon.

Question 6

Questions 5 to 9
Match the statements in items 5 to 9 with the appropriate lettered structure shown in the figure.

6. Gives rise to the choroid plexus

Answer 6

6–A. The tela choroidea gives rise to the choroid plexus.

Question 7

Questions 5 to 9
Match the statements in items 5 to 9 with the appropriate lettered structure shown in the figure.

7. Is derived from the alar plate

Answer 7

7–B. The inferior olivary nucleus is derived from the alar plate of the developing medulla.

Question 8

Questions 5 to 9
Match the statements in items 5 to 9 with the appropriate lettered structure shown in the figure.

8. Gives rise to motor neurons that innervate the tongue

Answer 8

8–D. The basal plate gives rise to the hypoglossal nucleus.

Question 9

Questions 5 to 9
Match the statements in items 5 to 9 with the appropriate lettered structure shown in the figure.

9. Gives rise to the solitary nucleus
   

Answer 9

9–E. The alar plate gives rise to the solitary nucleus.

Question 10

Questions 10 to 14
Match the statements in items 10 to 14 with the appropriate lettered structure shown in the figure.

10. Innervates the lateral rectus muscle

Answer 10

10–B. The GSE column innervates the lateral rectus muscle.

Question 11

Questions 10 to 14
Match the statements in items 10 to 14 with the appropriate lettered structure shown in the figure.

11. Gives rise to a parasympathetic nucleus
    

Answer 11

11–E. The GVE column gives rise to the superior salivatory nucleus of CN VII. This parasympathetic nucleus innervates the lacrimal, the sublingual, and the submandibular glands and also the palatine and nasal glands.

Question 12

Questions 10 to 14
Match the statements in items 10 to 14 with the appropriate lettered structure shown in the figure.

12. Gives rise to the cerebellum

Answer 12

12–A. The cerebellum is derived from the alar plate. The alar plate gives rise to the rhombic lip, which becomes the cerebellum.

Question 13

Questions 10 to 14
Match the statements in items 10 to 14 with the appropriate lettered structure shown in the figure.

13. Is derived from the alar plate

Answer 13

13–C. The pontine nuclei are derived from the alar plate.

Question 14

Questions 10 to 14
Match the statements in items 10 to 14 with the appropriate lettered structure shown in the figure.

14. Gives rise to motor neurons that migrate into the lateral pontine tegmentum

Answer 14

14–D. The SVE column gives rise to motor neurons that migrate into the lateral pontine tegmentum and become the facial nucleus, CN VII.