W19/L6: Embryology of NS

Question 1

What are the 3 layers of the trilaminar embryo?

Answer 1

Ectoderm
Mesoderm
Endoderm

Question 2

What is the process of neuralation?

Answer 2

The epithelial cells take on a special character, forming the neural plate.

The neural plate begins to invaginate to form a groove.

The “lips” of the groove fold in on themselves to make a tube lying below the remaining ectoderm

Question 3

What structure lies beneath the neural tube as it is developing?

Answer 3

The notochord

Question 4

In what order does the neural fold “zip up?”

Question 5

What does a failure in step 2 of neural fold closure cause?

Answer 5

Anecephaly

Question 6

What does a failure in step 5 of neural fold closure cause?

Answer 6

Spina bifida

Question 7

What nutrient is essential for neural fold closure?

Answer 7

Folate

Question 8

What are the three initial vesicles of the neural tube called?

Answer 8

Prosencephalon (forebrain)
Mesencephalon (midbrain)
Rhombencephalon (hindbrain)

Question 9

The prosencephalon splits into 2 segments, what are they called?

Answer 9

Telencephalon

Diencephalon

Question 10

How many segments does the rhombencephalon then split into

Answer 10

7 (**check this, as it also splits into metencephalon and myeloencephalon)

Question 11

The retinae form from

Answer 11

Outpouchings of the diencephalon called optic vesicle)