Module 1: Membrane Electrophysiology, Nerve and Synaptic Physiology

Question 0

Interaction between the chemical gradient and electrostatic force

Answer 0

Resting membrane potential

Question 1

T or F: Proteins are intrinsically negative and cannot readily pass through cell membrane.

Answer 1

T

Question 2

Combination if the following results in the RMP:

Answer 2

Potassium diffusion
Sodium diffusion
Na, K, ATPase

Question 3

Major determinant of RMP

Answer 3

Potassium

Question 4

T or F: In normal nerve fiber, the permeability of the membrane to K is about 100 times as great as to Na.

Answer 4

T

Question 5

Diffusion potential level across a membrane that exactly opposes the net diffusion of a particular ion

Answer 5

Nernst Equation

Question 6

Determined by the ratio of the concentrations of that specific ion on the two sides of the membrane

Answer 6

Nernst potential

Question 7

T or F: The greater the ratio, the greater the tendency for the ion to diffuse in one direction, and therefore the greater the Nernst potential requires to prevent additional net diffusion

Answer 7

T

Question 8

A phenomenon of solutions that contributes to the formation of an electrical potential across a cell membrane

Answer 8

Gibbs-Donnan equilibrium

Question 9

A rapid, all-or-none change in the membrane potential followed by a return to the resting membrane potential

Answer 9

Action potential

Question 10

_______________ in the plasma membrane are the basis for action potentials.

Answer 10

Voltage-dependent ion channels

Question 11

T or F: action potentials have stereotypical size and shape, are propagating, and are all-or-none.

Answer 11

T

Question 12

Requirements for an action potential

Answer 12

Lipid bilayer
Unequal distribution of ions
Selective permeability of membrane

Question 13

Makes the membrane potential LESS negative

Answer 13

Depolarization

Question 14

Makes the membrane potential MORE negative

Answer 14

Hyperpolarization

Question 15

Is the membrane potential at which the action potential is inevitable

Answer 15

Threshold

Question 16

The period during which another action potential cannot be elicited, no matter how large the stimulus

Answer 16

Absolute refractory period

Question 17

Begins at the end of absolute refractory period and continuous until the membrane potential returns to the resting level

Answer 17

Relative refractory period

Question 18

T or F: During relative refractory period, action potential can be elicited only if a larger than usual inward current is provided

Answer 18

T

Question 19

Occurs when the cell membrane is held at a depolarized level such that the threshold potential is passed without firing an action potential

Answer 19

Accomodation

Question 20

Propagation of action potential

Answer 20

Away from the stimulus

All or Nothing Principle

Question 21

T or F: Anterograde-away from the center, Kinesin

Answer 21

T

Question 22

T or F: Retrograde-towards the center, Dynein

Answer 22

T

Question 23

T or F: Nerve cells are capable of division.

Answer 23

F, they are incapable

Question 24

T or F: Nernst potential is potential OUTSIDE the membrane.

Answer 24

F, inside

Question 25

T or F: Sign of Nernst potential is (+) if ion diffuses from inside to outside.

Answer 25

T

Question 26

Glial cells that regulate microenvironment of the CNS

Answer 26

Astrocytes

Question 27

Produces myelin sheath

Answer 27

Schwann cells

Question 28

Glial cells that are capable of phagocytosis (macrophages)

Answer 28

Microglia

Question 29

Glial cells that are responsible for CSF production

Answer 29

Ependymal cells

Question 30

Signals are transferred form one cell to another via a synapse

Answer 30

Synaptic transmission

Question 31

Low resistance pathway between cells that allows current to flow directly from one cell to another

Answer 31

Electrical synapse

Question 32

Communication occur via intermediaries called neurotransmitters

Answer 32

Chemical synapse

Question 33

Key events in the presynaptic membrane

Answer 33

Action potential.. Entry of calcium.. Release of NT

Question 34

Key events in the postsynaptic membrane

Answer 34

Binding of NT.. | Response

Question 35

Opening of calcium channels Depressed conduction through chloride or potassium channels Various changes in the internal metabolism

Answer 35

Excitation

Question 36

Opening of Cl ion channels through the postsynaptic neuronal membrane Increase in conductance of potassium ions out of the neuron Activation of receptor enzymes

Answer 36

Inhibition

Question 37

Mediate chemical signaling between neurons

Answer 37

Neurotransmitters

Question 38

Criteria to be a neurotransmitter

Answer 38

There should be specific receptors for it The cell must be able to synthesize the substance Released on depolarization of the terminal There should be specific receptors

Question 39

Acetylcholine: Origin? Function?

Answer 39

Origin-basal forebrain (nucleus basilis) | Function-learning, memory

Question 40

Noreepinephrine: Origin? Function?

Answer 40

Origin-locus ceruleus | Function-arousal, wakefulness

Question 41

Dopamine: Origin? Function?

Answer 41

Origin-substantia nigra | Function-fine tuning of movements, reward

Question 42

Serotonin: Origin? Function?

Answer 42

Origin-median raphe | Function-mood, sleep

Question 43

Inputs that depolarize the postsynaptic cell, bringing it closer to threshold and closer to firing an action potential

Answer 43

Excitatory Postsynaptic Potentials (EPSP)

Question 44

EPSP is caused by opening of

Answer 44

Na and K channels

Question 45

Inputs that hyperpolarize the postsynaptic cell, moving it away from threshold and farther from firing

Answer 45

Inhibitory Postsynaptic Potentials (IPSP)

Question 46

IPSP is caused by opening of

Answer 46

Cl channels

Question 47

Process of adding up postsynaptic potentials and responding to their net effect

Answer 47

Summation

Question 48

Two types of summation

Answer 48

Temporal summation | Spatial summation

Question 49

Most prevalent NT in the brain; excitatory

Answer 49

Glutamate

Question 50

Dopamine: excitatory or inhibitory

Answer 50

Both

Question 51

Secreted by synapses in the spinal cord; inhibitory

Answer 51

Glycine

Question 52

GABA: excitatory or inhibitory

Answer 52

Inhibitory

Question 53

Controls long term behavior and memory; inhibitory

Answer 53

Nitric oxide

Question 54

T or F: Nitric oxide NEEDS receptor.

Answer 54

F