CNS development

Question 1

When does CNS development start?

Answer 1

3rd conception week

Question 2

What do genes determine?

Answer 2

the development of dendritic and axonal interconnections and development of synapses, complex chemical structures and neurotransmitters

Question 3

What is the time period for the embryonic period?

Answer 3

conception –> 8 weeks

Question 4

What occurs during the embryonic period?

Answer 4

migration of the cells through the primitive streak then rostral caudal migration determined by nodal signalling resulting in a 2 layered embryo

Question 5

What does gastrulation result in?

Answer 5

3 layered embryo

Question 6

What does the ectoderm develop into?

Answer 6

skin
hair
nails
neural tissue

(ecto - ectoutside you)

Question 7

What does the mesoderm develop into?

Answer 7

muscle
bone
cartilage
vascular system

(mesucle)

Question 8

What does the endoderm develop into?

Answer 8

gut
respiratory system

(endo - endoside you)

Question 9

When does the neural tube occur?

Answer 9

day 20-27

Question 10

What is the neural tube lined by?

Answer 10

neural progenitors - the ventricular zone

Question 11

What will the hollow center of the neural tube become?

Answer 11

ventricular system and the central channel of the spinal cord

Question 12

What will the anterior/rostral tube become?

Answer 12

brain

Question 13

What will the caudal tube become?

Answer 13

spinal cord

Question 14

What is the term given to failure of the brain vesicles to form?

Answer 14

holoprosencephaly

Question 15

What is PLPI?

Answer 15

responsible for the maintenance of myelin sheaths, oliogiodendrocyte development and axonal survival

Question 16

Where is PLPI located?

Answer 16

on the X chromosome

Question 17

What is Pelizaeus-Merzbacher disease?

Answer 17

X linked condition due to a mutation of PLPI.
It presents in early childhood with nstagmus (dancing eyes) hypotonia (floppy baby) and cognitive impairment
Progresses to spacitity and ataxia
Shorter life span

Question 18

What does the cerebrum develop from?

Answer 18

telencephalon - from the forebrain

Question 19

What does the eye cup, hypothalamus, thalamus and epithalamus develop from?

Answer 19

dicephalon - forebrain

Question 20

What does the midbrain develop from?

Answer 20

mencephalon - midbrain

Question 21

What does the cerebellum and pons develop from?

Answer 21

mentencephalon - hindbrain

Question 22

What does the medulla oblongata develop from?

Answer 22

myelencephalon - hindbrain

Question 23

What signals are used for neocortical patterning?

Answer 23

EMx2 and Pax6

Question 24

What does high EMx2 and low Pax6 encode for?

Answer 24

visual cortical neurones

Question 25

What does low EMx2 and high Pax6 encode for?

Answer 25

motor neurones

Question 26

At what weeks does the brain develop its primary, secondary and tertiary sulci?

Answer 26

primary - weeks 8-26
secondary - weeks 30-35
tertiary - weeks 36 onwards

Question 27

How do progenitor cells in the ventricular zone form neurones?

Answer 27

devide asymmetrically to create 1 progenitor cell and 1 neurone

Question 28

Where are progenitor cells found?

Answer 28

ventricular zone

Question 29

Where are neurones found?

Answer 29

the developing neocortex

Question 30

What do neurones develop once at their target cortical regions?

Answer 30

axons

dendrites

Question 31

What is the role of axons?

Answer 31

transmit signals from neurones

synapse when come in contact with another neurone

Question 32

What is the role of dendrites?

Answer 32

gather information and transmit to neurones

Question 33

What are the brain changes post natally?

Answer 33

myelination by oligodendrocyte progenitor cells. These develop processes which wrap around axons to form myelin sheaths
mainly first 2 years of life

Question 34

What adolescent changes occur in the brain?

Answer 34

increased gondal hormones after brain restructuring
gray matter maturation
mononuclear deprivation can alter patterns of organisation in the visual cortex