Nervous system structure through development

Question 1

What is derived from the ectoderm?

Answer 1

Skin and nervous system

Question 2

What is the neural plate?

Answer 2

Part of the ectoderm which becomes the nervous system

Question 3

What happens in neurulation?

Answer 3

• Neural plate folds to form neural groove and folds

- Further folding results in formation of neural tube and neural crest

Question 4

Which sections of the nervous system form from the neural tube? (2)

Answer 4

• CNS

- Ventricular system

Question 5

Which sections of the nervous system form from the neural crest? (1)

Answer 5

PNS

Question 6

What is the CNS and ventricular system derived from?

Answer 6

Neural groove

Question 7

What is the PNS derived from?

Answer 7

Neural crest

Question 8

What are somatic motor neurons?

Answer 8

Neurons that innervate muscles (muscle comes from the somites)

Question 9

How does closing of the neural tube happen?

Answer 9

Starts centrally and zips up and down from the middle

Question 10

What is anencephaly?

Answer 10

Failure to close the neural tube at the top

Question 11

What are the consequences of anencephaly?

Answer 11

Fatal

Question 12

What is spina bifida?

Answer 12

Failure to close the neural tube at the bottom

Question 13

Why are pregnant women advised to take folic acid in early pregnancy?

Answer 13

Reduces the chance of neural tube defects by 90%

Question 14

How does folic acid prevent neural tube defects?

Answer 14

Influences DNA synthesis

Question 15

What are the 3 primary brain vesicles which differentiate?

Answer 15

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

Question 16

What are the 3 secondary brain vesicles of the forebrain?

Answer 16

• Telencephalic vesicles
• Diencephalon
• Optic vesicles

Question 17

What do the telencephalic vesicles become?

Answer 17

Cerebral hemispheres

Question 18

What do the optic vesicles become?

Answer 18

Optic stalk and optic cup

Question 19

What does the optic cup become?

Answer 19

Retina

Question 20

What does the optic stalk become?

Answer 20

Optic nerve

Question 21

What are the key stages in development of the nervous system? (2)

Answer 21

• Neurulation

- Differentiation

Question 22

What happens during forebrain differentiation?

Answer 22

• Olfactory bulbs develop at the front of the cerebral cortex
• Ventricles start to develop
• Grey matter and white matter differentiate

Question 23

What does grey matter contain?

Answer 23

Neuronal cell bodies

Question 24

What does white matter contain?

Answer 24

Myelinated axons

Question 25

What does the basal telencephalon contain?

Answer 25

Basal nuclei

Question 26

What develops from the diencephalon? (2)

Answer 26

- Thalamus | - Hypothalamus

Question 27

What are the types of white matter tracks in the forebrain? (2)

Answer 27

- Corpus callosum | - Internal capsule

Question 28

What is the corpus callosum?

Answer 28

White matter track which carries information from one side of the brain to the other

Question 29

What is the internal capsule?

Answer 29

Carries information between the cerebral cortex and the thalamus/midbrain/pons/medulla etc.

Question 30

What are the sections of the midbrain? (3)

Answer 30

- Tectum (dorsal) - Tegmentum (ventral) - Cerebral aqueduct

Question 31

What is the midbrain involved in? (4)

Answer 31

- Visual processing - Auditory processing - Voluntary movement - Pain control

Question 32

What structures make up the hindbrain? (3)

Answer 32

- Pons - Medulla - Cerebellum

Question 33

What do the rhombic lips become?

Answer 33

Cerebellum

Question 34

What happens in hindbrain differentiation? (4)

Answer 34

- Rhombic lips form cerebellum - Fourth ventricle forms - Pons forms - Medulla and medullary pyramids form

Question 35

What are medullary pyramids?

Answer 35

White matter structures

Question 36

What are the main outer structures of the cerebellum? (3)

Answer 36

- Two hemispheres - Vermis - Folia

Question 37

What are folia?

Answer 37

Folds which increase the surface area of the cerebellum to allow it to have more neurons

Question 38

What are the main inner structures of the cerebellum (3)

Answer 38

- Cerebellar cortex - White matter - Deep cerebellar nuclei (grey matter)

Question 39

What are the pontine nuclei?

Answer 39

Nuclei in the pons involved in motor control

Question 40

What are the functions of the cerebellum?

Answer 40

Coordination of movement, balance and posture

Question 41

How is information processed in the cerebellum?

Answer 41

- Information from cerebral cortex feeds into pontine nuclei via internal capsule - Pontine nuclei project into cerebellar cortex - Purkinje cells integrate information and send back out via deep cerebellar nuclei

Question 42

What proportion of CNS neurons are in the cerebellum?

Answer 42

50%

Question 43

What proportion of CNS volume is the cerebellum?

Answer 43

10%