Neurophysiology Flashcards

(29 cards)

0
Q

What underlie electrical signaling?

A

Ionic forces!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What’s the big picture in order?

A

Nerve cells, parts of neuron, synapse, synaptic cleft, neuronal membrane, ion channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What kind of membrane do we have?

A

Semipermeable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What’s diffusion

A

Causes ions to flow from areas of high to low concentration, alone their concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define electrostatic pressure

A

Causes ions to flow towards oppositely charges areas (electrical gradient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are ion channels?

A

Proteins that down the membrane and allow ions to pass in and out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do gated channels open and close to?

A

Voltage changes, chemical, mechanical action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do neuronal cell membranes repel?

A

Water!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What surround ions? And what does that allow?

A

Ions are surrounded by water and therefor they can enter the cell only through w channel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are neuronal membranes not permeable to?

A

Neuronal membranes are not permeable to big negatively charged proteins (anions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are neurons selectively permeable to?

A

Neurons are selectively permeable to k+ . It an enter or leave the cell freely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does k+ do at rest?

A

At rest, k+ ions move into the negative interior of the cell because of electrostatic pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens as k+ ions build up inside the cell?

A

As k+ ions build up inside the cell, they also diffuse out alone the concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When does k+ reach equilibrium?

A

K+ reaches equilibrium is hen ion movement out is balanced by ion movement in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the membrane slightly permeable to?

A

The membrane is slightly permeable to sodium ions (Na+) so they slowly leak in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the sodium potassium pump do?

A

The sodium potassium pump puns Na+ out and k+ in, to maintain the resting potential

16
Q

How much of the brain spends running out he sodium potassium pump?

17
Q

The pump is good for leakage but not good for what?

A

Influx of sodium

18
Q

What’s does tetrodotoxin do?

A

Blocks nerve action by binding to/blocking pores of voltage gated, sodium channels in neuron membranes

19
Q

Why did the man who ate fugu feel like he was dying?

A

Because he was. His respiratory system was failing. The fish ovaries must be cleaned

20
Q

Where do graded potential take place?

21
Q

What happens as graded potential spread across the membrane?

A

They diminish. (“Ripples in a pond”)

22
Q

What occurs when the membrane reaches threshold?

A

It triggers an action potential, & inside of the cell briefly becomes positive

23
Q

T or F: neurons fire at full amplitude or not at all.

A

True. Thus, they cannot reflect increased stimulus strength

24
Action potentials increase in frequency with what?
Action potentials increase in frequency with increase stimulus strength
25
Where do action potentials start?
The axon hillock Don't give up! We are getting an a!
26
What do voltage gated na+ channels open in response to?
Initial depolarization
27
Once more voltage gated channels open what happens?
More Na+ ions enter until membrane potential reaches +40 mV
28
After membrane potential reaches +40, what's the third step?
Voltage gated na+ channels close