development

Question 1

What is a zygote undifferentiated_

Answer 1

a bunch of cells that don’t have specific function

Question 2

What is a zygote made of?

Answer 2

Egg & Sperm

Question 3

What does a zygote produce?

Answer 3

it produces all the cells in the body

Question 4

What is a blastula?

Answer 4

it is a ball of cells that are still unspecified

Question 5

What is the ectoderm?

Answer 5

the outer layer of the blastula

Question 6

How many tissues does the ectoderm develop to? What kind of tissues?

Answer 6

• develops into 2 tissues
  - skin cells
  - brain cells

Question 7

What is the Neural tube?

Answer 7

-it contains cells that divide & turns into the Central Nervous System
- it also becomes the back

Question 8

Where is the neural crest located?

Answer 8

Peripheral Nervous system

Question 9

Where is the Neural tube located?

Answer 9

Central Nervous System

Question 10

Where does our “gut” feelings reside?

Answer 10

• the Neural Crest
  - brain controls these cells, but they have a mind of their own

Question 11

What is the 1st stage of neural development?

Answer 11

Proliferation
- cell division occurs

Question 12

What is the 2nd stage of neural development?

Answer 12

Migration
- results in neuroblasts

Question 13

What are neuroblasts?

Answer 13

• Cells that are done dividing
• Their fate is to become neurons

Question 14

What occurs in migration?

Answer 14

• When each cell is done dividing, they move out
  - they keep moving until signals make it stop

Question 15

What is the 3rd stage of neural development?

Answer 15

Differentiation
- goes on for a long time
- cell bodies create its extensions
- when neuroblasts become a neuron

Question 16

How do target cells work?

Answer 16

• they release neurotrophic factors
  - they are sent back to the body to notify brain about synapse

Question 17

What kind of factors exist in target cells?

Answer 17

• NGF (nerve growth factor)
• BONF (brain derived neurotropic factor)

Question 18

What is the 4th stage of neural development?

Answer 18

Pruning & Cell Death

Question 19

What is pruning?

Answer 19

Pruning is when cells withdraw axons if no synapse

Question 20

What is apoptosis?

Answer 20

Genetic program for cell death too little neurotrophic factor
- clean cell death

Question 21

What is the 5th stage?

Answer 21

Myelination
- occurs when things are stabilized

Question 22

What are 2 kinds of glias?

Answer 22

• Oligodendroglia
  - only for CNS
• Schwann Cell
  - PNS

Question 23

What makes toxins different than toxicants?

Answer 23

• toxins are from nature
• toxicants are human made

Question 24

What can substances do to the brain?

Answer 24

• it can have permanent effects on it
• effects are greater during early development
• all stages of development are vulnerable

Question 25

What are the different windows for different development sections?

Answer 25

- Sensory function happens first - motor/language happens next - finally, higher cognition occurs

Question 26

Where are the cell bodies located in?

Answer 26

Gray matter

Question 27

What part of a cell is in the white matter?

Answer 27

the axons

Question 28

what kind of matter is in the corpus callosum?

Answer 28

White matter

Question 29

What is the corpus callosum?

Answer 29

- it is a huge tract - can be seen using transmission electron micrograph

Question 30

What is Amblyopia?

Answer 30

- eyes out of alignment - dominant eye takes over - common in babies - usually wears off

Question 31

What occurs in normal eyes when axons are competing for space?

Answer 31

- pruning occurs - allows each dendrite to sit in its own column

Question 32

What occurs in abnormal eyes when axons are competing for space?

Answer 32

- opened eye takes over the closed eyes space - doesn't allow dendrites to grow in closed eye - creates lazy eye

Question 33

What is the most common transmitter in the CNS?

Answer 33

Glutamate

Question 34

What is the AMPA receptor?

Answer 34

- it is an ionotropic receptor - when it is open, it allows ions to go through

Question 35

What do you need for a strong synapse?

Answer 35

- you need a lot of action potentials and NA+ - you need both axon terminals/ receptors

Question 36

How can NMDA be open?

Answer 36

- can only be opened if enough excitation from AMPA - also opens calcium - more ampa is released - stronger synapse

Question 37

What are the steps in NMDA coincidence detection?

Answer 37

1. several AMPA receptors in close proximity used simultaneously results in increased depolarization 2. NMDA opens & lens CA into the dendrite 3. CA starts a chemical cascade that results in more AMPA receptors being put into the membrane results in a STRONGER synapse

Question 38

How do dendrites respond to enriched environment?

Answer 38

- create more dendrites - result in better performances

Question 39

What happens to rats when going from adolescence to adulthood?

Answer 39

- loss of neurons between puberty & adulthood in medial prefrontal cortex & in amygdala

Question 40

What happens to rats and humans when going from adolescence to adulthood?

Answer 40

- synapses are lost in prefrontal cortex - myelination increases

Question 41

How does the adult brain change?

Answer 41

- proliferation in 2 brain areas only - increase in glias - no long axon growth - grow and prune dendrites - add and subtract synapses