neurocytology

Question 1

nervous system grows out of what embryonic structure?

Answer 1

CNS from the nueral plate

PNS and support cells from neural crest

neural tube- brain and spinal cord

Question 2

what is the life trojectory of neurons after they differentiate?

Answer 2

neurons stop dividing after they differentiate

Question 3

what is the difference between bipolar and pseudounipolar? where would you find them?

Answer 3

bipolar has the cell body right in the middle. pseudounipolar has it pushed to the side like. these are sensory nerves with pseudounipolar transfering info to the CNS

Question 4

what does the number of dendritic spines on a neuron tell you about it?

Answer 4

the more active the neuron the more dendritic spines it will have

Question 5

what is the initial segment?

Answer 5

the area right outside of the cell body (axon hillock). it hasa high concentration of voltage sensitive ion channels. Having voltage sensitive ion channels means it can fire action potentials the easiest

Question 6

proteins for info transport are only made in

Answer 6

the cell body. axons cannot make protiens

Question 7

what is the axon lacking that makes it imposible for it to make proteins?

Answer 7

axons do not have Nissel bodies on the cell body does. Nissle bodies are the RER of the cell body

Question 8

dendrites kinda could be mistaken for an axon. one is one way to tell them apart?

Answer 8

well they will all have the same cytoskeltal structures through out! BUT you can tell them apart because the dedrites HAVE nissle bodies! butt he axon does not

Question 9

how does microtubules and actin work together to get thngs to the terminus?

Answer 9

microtubules use kinesin to transport the cargo most of the way and then actin comes in and finishes the job

Question 10

which is more common in humans? chemical or electrical?

Answer 10

chemical synapse. electrical synapse are only found in develpment mostly

Question 11

components of a chemical synapse?

Answer 11

presynaptic element

synaptic clept

post synaptic element

Question 12

what is the name of the location where the synaptic vesicles are released?

Answer 12

active zone. and it looks like this

Question 13

which- the pre or post synaptic neuron will have all the synaptic vesicles in it under EM

Answer 13

the pre will be the one with the big RER and all the vesicles. it will be held together by a synapse

Question 14

when the action potention reaches the synapse, what steps happen in order to get the vessicle to move to the active zone?

Answer 14

action potention gets there

calcium is released into the presynaptic vesicle

binds with calmodulin

Ca and calmodulin activate a kinase that phosphorylates Synapsin 2 (tasked with holding the vesicle far from active zone)

when phosphirylated, it releases the vesicle

vesicle travels to active zone

Question 15

what are the three ways the neurotransmitters in the synaptic cleft can be gotten rid of?

Answer 15

1. degraded by enzymes
2. can be taken up by the presynaptic neuron and recycled
3. taken up by glial cells
4. sometimes they diffuse away

Question 16

where does the location the axon synapsed on the neuron tell you about the importance of that signal?

Answer 16

we know axons as they synapse mostly with dendrites but they can really synapse anywhere. The closer the axon synapses to the cell body, the more important ths it is.

Question 17

what is the concept of synaptic veracity

Answer 17

you have the cell body lie far away from the what they are signalling

Question 18

what causes anterograde transneuronal degeneration vs anterograde?

Answer 18

retrograde is caused by the neuron being cut off from its source of trophic substances (neutrients) anterograde is when the axon is lysed and the axon cant get protiens from the cell body and the cell body cannot get neutrients from the axon terminal