Week 1: Lecture/TBL

Question 1

At which week in embryogenesis, does the neural plate begin formation?

Answer 1

Week 3

Question 2

Which nutrient is necessary for neural development during pregnancy?

Answer 2

B9: Folate

Question 3

From which layer does the neural tube develop (ectoderm, mesoderm, endoderm)?

Answer 3

Ectoderm

Question 4

From which layer does the notochord and somites develop (ectoderm, mesoderm, endoderm)?

Answer 4

Mesoderm

Question 5

Dandy Walker syndrome affects which level of the nervous system?

Answer 5

Cerebellum

Question 6

Which anatomical area of the spinal cord is responsible for maintaining the sympathetic tone for the body?

Answer 6

Intermediate horn of the thoracic spinal cord

Question 7

Define spinal dysraphism

Answer 7

Spina bifida

Question 8

What tissues/organs are produced from the mesoderm?

Answer 8

CV system, muscles, bones

Question 9

What organs are produced from the endoderm?

Answer 9

Liver, lungs, GI tract

Question 10

What tissues/organs are produced from the surface ectoderm?

Answer 10

Anterior pituitary, lens, cornea

Question 11

What tissues/organs are produced from the neural tube?

Answer 11

brain spinal cord, post pituitary, retina

Question 12

What tissues/organs are produced from the neural crest?

Answer 12

Autonomic, sensory nerves, skull

Question 13

What are the steps of neural development?

Answer 13

1. Notochord secretes signaling molecules (Sonic Hedgehog protein)
2. Molecules induce overlying ectoderm to become neuroectoderm
3. Neuroectoderm becomes neural plate
4. Neural plate folds to become the neural tube and neural crest cells

Question 14

What are the 3 primary vesicles of the neural tube?

Answer 14

Forebrain (prosencephalon), Midbrain (mesencephalon) and Hindbrain (rhombencephalon)

Question 15

What are the 5 secondary vesicles of the neural tube?

Answer 15

Telecephalon, Diencephalon, Mesencephalon, Metencephalon, Myelencephalon

Question 16

When do the three primary brain vesicles form embryonically?

Answer 16

3-4 weeks

Question 17

When do the five secondary brain vesicles form embryonically?

Answer 17

5 weeks

Question 18

Name 3 types of neural congenital defects

Answer 18

1. Neural tube defects (Spina bifida, Anencephaly, Encephalocele)
2. Cephalic disorders (holoprosencephaly)
3. Posterior Fossa Defects (Chiari malformations, Dandy Walker)

Question 19

Define what occurs in spina bifida

Answer 19

caudal neuropore fails to close posteriorly; bones do not close around the spinal cord/meninges

Question 20

Define what occurs in Anencephaly

Answer 20

rostral neuropore fails to close anteriorly; absence of major portions of brain/skull

Question 21

Neural Tube Defect Risks

Answer 21

*decrease in folic acid
*Type 1 diabetes
*Obesity
*Valproic acid/carbamazepine (antiseizure meds)

Question 22

Describe a spina bifida occulta

Answer 22

*Bones fail to fuse normally
*Meninges and spinal cord in normal position
*Abnormal tuft of hair or dimple over spinal cord

Question 23

Describe a meningocele

Answer 23

*Meninges bulge out
*Spinal cord intact

Question 24

Describe a myelomeningocele

Answer 24

*Both meninges and spinal cord bulge out of spine
*Often has Chiari malformation as secondary

Question 25

Describe Anencephaly

Answer 25

*forebrain/brainstem exposed in utero *Lethal *Polyhydramnios present

Question 26

What does an ultrasound show in anencephaly?

Answer 26

open calvaria (formation of skull); frog-like appearance of fetus

Question 27

Describe encephalocele

Answer 27

brain or meninges herniate through the skull; usually in occipital area