Neurodevelopment

Question 1

what is the Germinal stage?

Answer 1

when the nuclei of the egg and sperm fuse and form a zygote. At 12 hours cleavage occurs - zygote divides to form cluster of cells called morula

Question 2

what is morula?

Answer 2

a cluster of cells formed from the zygote undergoing cell division. occurs in the germinal stage

Question 3

what is a blastocyst?

Answer 3

the morula continues to divide and forms a blastocyst

Question 4

when does the embryonic stage begin?

Answer 4

once implantation in the uterus occurs

Question 5

what is gastrulation?

Answer 5

an early phase of the embryonic stage

Question 6

what are the 3 layers the embryonic disc

?

Answer 6

ectoderm, mesoderm, endoderm

Question 7

what does the ectoderm eventually become, and how?

Answer 7

the nervous system, by folding in on itself to form the neural tube

Question 8

what are the 6 stages of brain development in order?

Answer 8

cell birth, cell migration, cell differentiation & maturation, synaptogenesis and synaptic pruning, cell death, myelination

Question 9

how do cells migrate out of the ventricular zone?

Answer 9

chemical signals - immonuglobulins & cytokins

physical support - radial glia

Question 10

what happens if cells fail to migrate the ventricular zone?

Answer 10

there may be serious effects eg. dyslexia and epilepsy

Question 11

how do cells differentiate?

Answer 11

they express different genes through the growth of axons and dendrites which give them a distinctive shape

Question 12

what are the two types of dendritic development?

Answer 12

dendritic arborization (branching), and growth of dendritic spines

Question 13

what is the growth cone?

Answer 13

the growing end of the axon

Question 14

what are filopodia?

Answer 14

thin extensions that growth cones develop

Question 15

what are the names of the chemicals from target sites that attract the growth cones?

Answer 15

cell adhesion molecules (CAM)

tropic molecules

Question 16

what is synaptic pruning?

Answer 16

where the synapses that are not used are eliminated and active synapses are maintained and strengthened

Question 17

what is synaptic rearrangement?

Answer 17

where synapses take over other synapses, can happen at any stage of life and occurs as a result of experience

Question 18

what are the two types of cell death and what are they?

Answer 18

apoptosis - programmed cell death, a natural process and little damage is caused
necrosis - a result of injury, cell bursts and causes damage to surrounding neurons

Question 19

what is apoptosis?

Answer 19

programmed cell death, it is a natural process and causes little to no damage to surrounding neurons

Question 20

what is necrosis?

Answer 20

cell death as a result of injury, the cell ‘bursts’ and causes alot of damage to surrounding neurons

Question 21

what is myelination?

Answer 21

a process where glia form the fatty sheath that covers the axons of neurons

Question 22

what does the myelin sheath do?

Answer 22

speeds up transmission of neural impulses

Question 23

what is collateral sprouting?

Answer 23

sprouting of non-damaged axons to fill vacant synapses, is a part of recovery after injury

Question 24

what is brain plasticity

Answer 24

it’s ability to adapt as a result of experience and injury

Question 25

what did Burton 2002 find?

Answer 25

that the occipital cortex in blind people was activated when asked to feel braille

Question 26

what is a critical period?

Answer 26

a period during which the brain is most sensitive to a specific experience

Question 27

what is epigenetics?

Answer 27

the study of the interaction of gene expression and the environment