Development of the Nervous System Flashcards Preview

ESA4 - Nervous System > Development of the Nervous System > Flashcards

Flashcards in Development of the Nervous System Deck (25):
1

What induces neurulation?

Notochord

2

What is neurulation?

Formation of the neural tube from the ectoderm, following gastrulation

3

What is the neural plate?

Thickening of neuroectoderm

4

As the lateral edges of the neural plate elevate, what is the depressed mid-region called?

Neural groove

5

How do the neural folds create the neural tube?

Approach each other in the midline and fuse to produce the neural tube

6

What do neural tube defects result from?

Failure of the neural tube to close which can occur caudally or cranially

7

What does a cranial neural tube defect result in?

Anencephaly

8

What does a caudal neural tube defect result in?

Spina bifida

9

What is hydrocephalus?

An accumulation of CSF within the brain

10

What is rachischisis?

Result of failure of neural fold elevation, no neural tube formed

11

How can NT defects be diagnosed and prevented?

USS, raised maternal serum a-fetoprotein (embryonic proteins lead into amniotic fluid in open defects)

Folic acid given pre-conceptually and for the first trimester reduces incidence by 70%

12

What does the prosencephalon become?

Forebrain

13

What does the mesencephalon become?

Midbrain

14

What does the rhombencephalon become?

Hindbrain

15

At 5 weeks of development, five secondary brain vesicles are formed. What are these?

Telencephalon, diencephalon (forebrain)
Mesencephalon (midbrain)
Metencephalon, myelencephalon (hindbrain)

16

What is the mature derivative of the telencephalon?

Cerebral hemispheres

17

What is the mature derivative of the diencephalon?

Thalamus

18

What is the mature derivative of the mesencephalon?

Midbrain

19

What is the mature derivative of the metencephalon?

Pons, cerebellum

20

What is the mature derivative of the myelencephalon?

Medulla oblongata

21

Is the alar plate sensory or motor?

Sensory (dorsal)

22

Is the basal plate sensory or motor?

Motor (ventral)

23

What are neural crest cells?

Cells of the lateral border of the neuroectoderm tube that become displaced and enter the mesoderm and undergo epithelial to mesenchymal transition

24

Give some examples of neural crest derivatives

Schwann cells, glial cells, odontoblasts, C cells of thyroid gland, melanocytes, adrenal medulla

25

What is Hirschsprung's disease?

No enteric ganglia - aganglionic megacolon

Blockage, faeces stuck in bowels