Nervous System I

Question 1

Hyperpolarization makes the membrane potential ______ polarized

Answer 1

More

Question 2

Two types of changes in membrane potential that transmit information

Answer 2

1. Graded potentials

2. Action potentials

Question 3

True or false: the amplitude of an action potential is always the same

Answer 3

True

Question 4

Depolarize got makes the membrane potential _____ polarized

Answer 4

Less

Question 5

A small deviation from resting potential

Answer 5

Graded potentials

Question 6

Threshold for action potential

Answer 6

-55mV

Question 7

Why do action potentials propagate in one direction?

Answer 7

The refractory period means that action potentials cannot travel backwards

Question 8

Four terms used to describe direction of changes in membrane potential relative to rest

Answer 8

1. Depolarization
2. Overshoot
3. Repolarization
4. Hyperpolarization

Question 9

The gates of a _____________ ion channel open in response to a change in membrane potential

Answer 9

Voltage-gated

Question 10

Velocity of action potential depends on…

Answer 10

Fibre diameter and myelination

Question 11

Two main divisions of the efferent PNS

Answer 11

1. Somatic nervous system

2. Autonomic nervous system

Question 12

Effectors of the somatic nervous system

Answer 12

Skeletal muscle

Question 13

The gates of ______ ion channels randomly alternate between open and closed positions

Answer 13

Leak

Question 14

What cells assist in regeneration of damaged neurons in the PNS?

Answer 14

Schwann cells

Question 15

Myelinated axons have a ______ propagation speed

Answer 15

Faster

Question 16

What type of ion channels are responsible for action potentials

Answer 16

Voltage-gated ion channels

Question 17

Four main types of ion channels

Answer 17

1. Leak
2. Ligand-gated
3. Mechanically-gated
4. Voltage-gated

Question 18

Divisions of the autonomic nervous system

Answer 18

1. Sympathetic nervous system
2. Parasympathetic nervous system
3. Enteric nervous system

Question 19

The resting membrane potential of a cell at rest has a more ________ charge inside compared to the outside

Answer 19

Negative

Question 20

_____________: the force generated by the separation of charge

Answer 20

Voltage

Question 21

How do local anaesthetics such as noviciate and xylocaine prevent pain?

Answer 21

They block Na+ channels, preventing action potentials and stopping afferent pain signals reaching CNS

Question 22

Effectors of the enteric nervous system (2)

Answer 22

Smooth muscle and glands of GI tract

Question 23

The gates in a ___________ ion channel open and close in response to a specific ligand

Answer 23

ligand-gated channels

Question 24

Effectors of the sympathetic and parasympathetic nervous systems (3)

Answer 24

Smooth muscle, cardiac muscle, and glands

Question 25

How are graded potentials caused?

Answer 25

Localized ligand-gated or mechanically-gated ion channels

Question 26

Two divisions of the afferent PNS

Answer 26

1. Somatic senses | 2. Special senses

Question 27

When a charge/force has the ability to move charge, it is referred to as...

Answer 27

Potential

Question 28

Concentrations of sodium and potassium inside verses outside an excitable cell

Answer 28

High [K+]in | High [Na+]out

Question 29

_____ fibre diameter axons have faster propagation

Answer 29

Large

Question 30

Why does myelination increase propagation speed?

Answer 30

Saltatory conduction

Question 31

Order of voltage-gated K+ and Na+ opening as action potential is triggered

Answer 31

Na+ channels open as threshold is hit —> causes depolarization K+ channels open at reversal —> causes repolarization; delayed closure causes hyperpolarization

Question 32

Gates of __________ ion channels open/close in response to a mechanical stimulation (ie. touch, pressure, tissue stretching, vibration)

Answer 32

Mechanically-gated

Question 33

Define plasticity vs repair

Answer 33

Plasticity: ability to change throughout life Repair: regeneration after damage

Question 34

If charge is allowed to move, it is called....

Answer 34

Current

Question 35

How do Schwann cells assist in regeneration

Answer 35

Schwann cells form regeneration tube, which guides and stimulated regrow the of the axon