8.1

Question 1

how many neurons in the body?

Answer 1

10^12

Question 2

neuron structure

Answer 2

body
dendrites
axon

Question 3

action of myelin

Answer 3

lipid insulator
increases membrane resistance
force current to flow along the axon interior

Question 4

what are Nodes Of Ranvier?

Answer 4

small breaks every 1-2 mm

saltatory conduction

Question 5

Aa fiber conduction velocity

Answer 5

70-12 m/s

Question 6

Ab fiber conduction velocity

Answer 6

30-70 m/s

Question 7

A delta fiber conduction velocity

Answer 7

5-30 m/s

Question 8

C fiber conduction velocity

Answer 8

0.5-2.5 m/s

Question 9

which fiber is madiator for pain?

Answer 9

A delta

also C

Question 10

whar are the 3 ways of coding information in the NS?

Answer 10

1. labeled line (like the fibers carring info about vision)
2. spatial map (2 neighboring points on the skin)
3. temporal pattern (timing of AP)

Question 11

we do summation of

Answer 11

EPSP

IPSP

Question 12

what is the depolarize rannge of EPSP?

Answer 12

1-5 mV

lasts for ms

Question 13

Most common NT of EPSP?

Answer 13

Glu

Question 14

What are the 2 R for Glu?

Answer 14

Ionotropic (AMPA,NMDA)

Metabotropic (mGluR 1-8)

Question 15

Describe AMPA R

Answer 15

Permeable for univalent cations
Na+ influx
Can lead to Depol.

Question 16

Describe NMDA R

Answer 16

Permeable for univalent cations and Ca++
Na+ and Ca++ influx 
Depol. must have already happen in order for them to open
stronger response
(Long Term Potentiation)

Question 17

Describe Metabotropic (mGluR 1-8)

Answer 17

all Gi

except 1 and 5 which are Gq

Question 18

most frequent NT for IPSP

Answer 18

GABA

Question 19

R types for GABA?

Answer 19

GABA A

GABA B

Question 20

Describe GABA A Receptor

Answer 20

pentameric ligand gated Cl- channel

Question 21

Describe GABA B Receptor

Answer 21

Gi coupled
they open inward rectifying K+ channels (Kir)
create slower Hyperpolarization

Question 22

2 ways for summation of PostSynaptic Summation

Answer 22

Temporal

Spatial

Question 23

describe Temporal summation

Answer 23

amount of time btw. the PSP’s
we need them to be close in order to sum them
A+A (after some time)

Question 24

describe Spatial summation

Answer 24

summation of PSP’s from different input at the same time

A+B

Question 25

AP frequency is directly proportional to

Answer 25

the summed PSP Amplitude

Question 26

what is non-adapting neuron?

Answer 26

quickly depolarize and repolarize | can maintain high frwquency of AP

Question 27

what is adapting neuron?

Answer 27

also havs slowly-activating voltage gated K+ channels | it provides resistance to depolarization

Question 28

what is rythmic bursting neuron?

Answer 28

have voltage gated Ca++ channels | and Ca++ activated K+ channels (hyperpolarization of the cell)

Question 29

what is burst neuron?

Answer 29

in thalamus neurons | EPSP leads to T-Type channel opening

Question 30

what is synaptic placticity?

Answer 30

tha ability of synaps to change their strength

Question 31

describe what is potential?

Answer 31

difference in charge btw outside and inside

Question 32

how does Long Term Potentiation can increase synaptic strength?

Answer 32

high frequency stimulation -> AMPA-R activity -> depol -> NMDA-R activity -> [Ca++] high -> CAM-Kinase -> AMPA-R phosphorylation and more activation

Question 33

how many Glial cells?

Answer 33

x10 more than neurons

Question 34

different types of Astrocytes?

Answer 34

``` fibrous protoplasmic radial glial Muller Bergmann (cerebellum) ```

Question 35

function of astrocytes?

Answer 35

1. provide fuel 2. rgulate [K+] 3. regulatr pH of EC fluid 4. take up Glu 5. modulate cerebral blood flow

Question 36

describe how astrocytes provide fuel for neurons?

Answer 36

release lactate through MCT-1 neuron use MCT-2 to bring lactate inside convert it back to pyruvate

Question 37

why is it possible to have K+ channels for influx in the astrocytes?

Answer 37

astrocytes have very negative membrane potential | so K+ wants to travel inside

Question 38

describe how astrocytes modulate cerebral blood flow?

Answer 38

Glu activates mGluR-1 or mGluR-5 -> Gq -> Ca++ up -> PGE2 and NO release -> vasodilation -> more blood flow to the active neurons

Question 39

what makes Myelin and where

Answer 39

Oligodendrocytes- CNS | Schwann cells- PNS

Question 40

what are the macrophages of the CNS

Answer 40

Microglial cells

Question 41

which cells produce the CSF?

Answer 41

Ependymal cells