Neurulation and Neural Crest

Question 1

What is meningocele spina bifida?

Answer 1

spinal cord in correct place; cyst of CSF and meninges outside of body; pts may or may not have deficits

Question 2

What vitamin deficiency causes spina bifida?

Answer 2

folic acid

Question 3

What does the ectoderm just lateral of the neural groove (medium amount of SHH) turn into?

Answer 3

neural crest –> migrates down to become spinal ganglion

Question 4

What does the most medial ectoderm above the notochord become?

Answer 4

neural groove –> neural tube (neuroectoderm)

Question 5

What are cranial neural crest derivatives?

Answer 5

neurons and glia of cranial gangia
cartilage and bone
connective tissue

Question 6

What does the posterior part of the pituitary gland come from?

Answer 6

neural tube

Question 7

What is the pachymeninx?

What is it made of and give rise to?

Answer 7

structure that gives rise to DURA mater

made of MESOderm

Question 8

What are trunk neural crest derivatives?

Answer 8

pigment cells
sensory neurons and glia
sympathoadrenal cells
schwann cells

Question 9

What germ cells do pigment cells come from?

Answer 9

neural crest

Question 10

What is the region of secondary neurulation? What happens there?

Answer 10

caudal eminence: fuses with caudal neuropore –> lumbar and coccyx regions

Question 11

What tissue gives rise to the arachnoid and pia mater?

Answer 11

neural crest

Question 12

What is encephalocele?

what is it due to?

Answer 12

cyst on head; can be with or without brain tissue

Due to failure of rostral neural pore closure

Question 13

What does the anterior part of the pit gland come from?

Answer 13

surface ectoderm

Question 14

What does the most lateral ectoderm become?

Answer 14

surface ectoderm –> developing epidermis

Question 15

What germ layer do epithelium of GI tract, liver, pancreas, and bladder come from?

Answer 15

endoderm

Question 16

When does the caudal neuropore close?

Answer 16

day 28

Question 17

What is myelocele spina bifida?

Answer 17

open spinal cord out of body; motor and sensory deficits

Question 18

What is memingomyelocele spina bifida?

Answer 18

neural tube/spinal cord, meninges, and csf are protruding out of body; motor and sensory defects

Question 19

What germ cells does the retina come from?

Answer 19

neural tube

Question 20

When does the rostral/ cephalic neuropore close?

Answer 20

day 25

Question 21

What is anencephaly?

What is it due to?

Answer 21

loss of neocortex and calvera (open brain); incompatible with life
due to failure of rostral neural pore closure

Question 22

What is the meninx primitiva?

What is it made of?

Answer 22

structure that gives rise to the meninges (dura, arachnoid, pia)
made up of sclerotome from mesoderm and neural crest cells

Question 23

What is the significance of alpha fetoprotein in spina bifida

Answer 23

levels of alpha FP increase when there are neural tube defects –> can be detected in amniocentesis

Question 24

What is spina bifida occulta?

Answer 24

least severe spina bifida; vertebral arch isn’t closed and there is often a tuft of hair; no symptoms

Question 25

What germ layer do epithelial parts of the trachea, bronchi, and lungs come from?

Answer 25

endoderm

Question 26

What is hirschspring’s disease/aganglionic colon?

Answer 26

defect where autonomic sensory nerves don’t innervate the colon –> can’t poop and colon keeps expanding
problem with trunk neural crest cell migration

Question 27

What signal does the notochord release to induce the neural plate?

Answer 27

Sonic Hedgehog

Question 28

What types of nerves come from neural crest?

Answer 28

SENSORY and cranial

Question 29

What germ layer does the pharynx and thyroid gland come from?

Answer 29

endoderm