Generation of the AP and transmission of impulses

Question 1

Ions cross the membrane via channels or pumps that are formed by ____ in the membrane.

Answer 1

proteins

Question 2

Ion ___:

• actively move ions AGAINST the concentration gradient
• creates ion concentration gradients

Answer 2

Transporters

Question 3

Ion ___:

• allows ions to diffuse down the concentration gradient
• causes selective permeability to certain ions

Answer 3

channels

Question 4

Type of channel:

• The channel opens when a substance binds to a receptor
• involves a protein or receptor attached to either the extracellular or intracellular portion of the membrane
• SELECTIVE

Answer 4

ligand gated channel

Question 5

Ach at the NMJ is an example of a ____ gated channel.

Answer 5

ligand

Question 6

Type of channel:

• opens when a membrane voltage reaches a certain value
• SELECTIVE

Answer 6

voltage gated channel

Question 7

(true/false) Voltage gated channels have different voltages to change the permeability of the membrane depending on the channel.

Answer 7

True

Question 8

Type of channel:

• allows ions to flow dependent on stretch, pressure, and temperature
• SENSORY receptor involvement (hair follicle)

Answer 8

mechanically gated channel

Question 9

Potassium (K+) is greater on the (inside/outside) of the cell

Answer 9

inside

Question 10

Sodium (Na+) is greater on the (inside/outside) of the cell

Answer 10

outside

Question 11

Chloride (Cl-) is greater on the (inside/outside) of the cell

Answer 11

outside

Question 12

Organic anions (-) are greater on the (inside/outside) of the cell

Answer 12

inside

Question 13

Potassium (K+) wants to go (in/out) of the cell

Answer 13

out

Question 14

Sodium (Na+) wants to go (in/out) of the cell

Answer 14

in

Question 15

Chloride (Cl-) wants to go (in/out) of the cell

Answer 15

in

Question 16

(true/false) Organic anions cannot move along a diffusional gradient because they cannot pass through a membrane or channel

Answer 16

true

Question 17

Normally, a neuron is more (negative/positive) compared to its extracellular component.

Answer 17

negative

Question 18

The membrane potential at which electrical forces equally counter the diffusional forces

Answer 18

equilibrium potential

Question 19

Membrane potential for Potassium is ___ mV.

Answer 19

-75

Question 20

Membrane potential for sodium is ___ mV.

Answer 20

55

Question 21

The sodium potassium pump transfers __ Na+ into the EXTRACELLULAR space while ___ K+ is transported to the INTRACELLULAR space.

Answer 21

3, 2

Question 22

What is the resting membrane potential?

Answer 22

-65 to -75

Question 23

A rapid change in membrane potential

Answer 23

action potential

Question 24

Where is an action potential initiated?

Answer 24

axon hillock

Question 25

Non-myelinated axons have (slow/fast) conduction

Answer 25

slow

Question 26

(True/false) The diameter of an axon is a factor in how quickly an impulse travels.

Answer 26

True

Question 27

A larger diameter of an axon results in a (slower/faster) transmission of an impulse

Answer 27

faster

Question 28

(true/false) When myelin is disrupted with disease, transmission of impulses are delayed or absent with loss or poor timing of information.

Answer 28

true

Question 29

When damage to an axon/myelin occurs, re-myelination MAY occur but the nodes are now ___ together causing a (slower/faster) transmission of impulses

Answer 29

closer, slower

Question 30

Low sodium

Answer 30

hyponatremia

Question 31

An increase in sodium causes ____ and ___ in cells.

Answer 31

swelling, demyelination

Question 32

Low calcium

Answer 32

hypokalemia

Question 33

Electrolyte that stabilizes voltage gated channels

Answer 33

calcium

Question 34

hypokalemia will cause ___ of the nervous system.

Answer 34

excitement

Question 35

A decrease in ___ causes weakness.

Answer 35

potassium

Question 36

What toxins inhibits/blocks sodium channels?

Answer 36

tetrodotoxin, saxotoxin