Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Integrative Physiology > Neuronal Excitability and Nervous System > Flashcards

Neuronal Excitability and Nervous System Flashcards

1
Q

Afferent division of nervous system

A

Somatic and special senses

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

Efferent division of nervous system

A

Control muscles, motor output

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

Neuron parts

A

Axon terminal, axon, cell body, dendrites

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

Interneurons

A

Association neurons

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

Three classifications of neurons

A

Sensory, interneuron, efferent

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

Efferent neurons

A

Motor neurons

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

Dendrites

A

Sensory receptors (receive signals)

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

Glial cell types

A

Oligodendrocytes, microglia, astrocytes, ependymal cells

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

Satellite glial cell function

A

Support neuron cell bodies

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

Glial cell function

A

Provide physical and biochemical support to neurons

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

Which glial cells form myelin shealths?

A

Oligodendrocytes (schwann cells)

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

Which glial cells help form the blood brain barrier, provide substrates for ATP production, secrete neurotrophic factors, and take up K+ , water and neurotransmitters?

A

Astrocytes

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

Ependymal cell functions

A

Source of neural stem cells, create barriers between compartments

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

Which two glial cells are a source of neural stem cells?

A

Astrocytes, ependymal cells

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

Which glial cells are the most numerous?

A

Astrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Microglia function

A

Phagocytes (scavengers) –> remove debris, damaged cells, pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Pia matter

A

Inner covering around the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Node of Ranvier

A

Areas of an axon between myelin sheath (between shwann cells) –> gaps in myelination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Functions of myelin sheath

A

Electrical insulation, found in CNS and PNS, makes up white matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Difference between schwann cells and oligodendrocytes

A

Oligodendrocytes = CNS
Schwann cells = PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Resting membrane potential

A

Electrical potential difference across plasma membrane (negative inside cell, positive outside of cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Leak channels

A

Randomly open and close, allowing K+/Na+ to penetrate the membrane and move outside/inside of the cell (down concentration gradient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Ligand-gated channel

A

Opens or closes in response to specific ligand (chemical) stimulus (allows Na+ and K+ to move down concentration gradients)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Mechanically-gated channel

A

Open or close in response to touch, pressure, tissue stretching, vibration (mechanical stimulation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Voltage-gated channel

A

Opens in response to change in membrane potential (voltage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Nernst Equation

A

Describes membrane potential that a single ion would produce if the membrane were permeable to only that ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Influence of membrane potential

A
  1. concentration gradient of ions
  2. membrane permeability to those ions
28
Q

GHK Equation

A

Predicts membrane potential that results from the contribution of all ions that can cross the membrane –> resting membrane potential is determined by the combined contributions of the (concentration gradient x membrane permeability) of each ion

29
Q

Resting membrane potential is primary determined by

A

K+ concentration gradient (due to K+ leak channels), cell’s resting permeability to K+, Na+, Ca+

30
Q

Depolarization

A

Membrane potential becomes less polarized (less negative)

31
Q

Hyperpolarizing

A

Membrane potential becomes more polarized (more negative)

32
Q

Graded potentials

A

Local changes in membrane potential, decrease in strength as they spread out from the point of origin (large stimulus= large potential, vice versa)

33
Q

Graded potentials can be…

A

Hyperpolarizations or depolarizations

34
Q

Suprathreshold graded potential

A

Will trigger an action potential

35
Q

Subthreshold graded potential

A

Is not strong enough to generate an action potential because it is subthreshold when it reaches the trigger zone

36
Q

Strength of graded potential is determined by

A

The strength of the stimulus

37
Q

Summation

A

Multiple graded potentials can increase the strength of the signal - signals can come from multiple neurons, if sum of graded potentials reaches threshold, will cause an action potential

38
Q

Strength of initial depolarization in a graded potential is determined by

A

How much charge enters the cell

39
Q

Why do graded potentials lose strength as they move through the cell?

A

Current leak, cytoplasmic resistance

40
Q

Trigger zone

A

Axon hillock

41
Q

SEQ action potential

A
  1. Resting membrane potential
  2. Depolarizing stimulus
  3. Membrane depolarizes to threshold, Na+ enters the cell, K+ starts to leave the cell SLOWLY
  4. Rapid Na+ entry depolarizes cell
  5. Na+ channels close, K+ channels open
  6. K+ moves from cell to extracellular fluid
  7. K+ channels remain open and K+ continues to leave, hyperpolarizing cell
  8. Voltage-gated K+ channels close, less K+ leaks from cell
  9. Cell returns to resting ion permeability and resting membrane potential
42
Q

Absolute refractory period

A

When the action potential is peaking, zero cell excitability (because cell is being excited already)

43
Q

Two factors that influence AP speed

A
  1. Diameter of axon (larger= faster)
  2. Ion leakage (less leaks= faster)
44
Q

Why do myelinated axons have faster action potentials?

A

Only nodes have Na+ channels, action potential jumps from node to node and covers more ground in less time

45
Q

Demyelinated axons

A

Slows conduction of AP by current leaking out of axon where myelination was previously, causes degenerative diseases (ex. MS)

46
Q

Saltatory conduction

A

Jumping of AP from node to node in myelinated axons

47
Q

Hyperkalemia

A

Increased blood K+ concentration, brings membrane closer to threshold (more positive) and stimulus that were previously subthreshold will trigger action potentials

48
Q

Hypokalemia

A

Decreased blood K+ concentration, hyperpolarizes membrane (more negative) and decreases likelihood of firing action potential

49
Q

Synapses

A

Pass electrical signals between neurons by neurotransmitters

50
Q

What ion is responsible for the release of neurotransmitters?

A

Ca2+

51
Q

Seven classes of neurocrines

A
  1. Acetylcholine
  2. Amines
  3. Amino acids
  4. Purines
  5. Gases
  6. Peptides
  7. Lipids
52
Q

Acetylcholine (Ach)

A

Synthesized from choline and acetyl coA

53
Q

Cholinergic neurons

A

Release and bind Ach

54
Q

Amine neurotransmitters

A

Dopamine, norepinephrine, epinephrine (all derived from Tyrosine), others include serotonin (Tryptophan), Histamine (Histidine)

55
Q

Amino acid neurotransmitters

A

Glutamate (excitatory), Aspartate (excitatory), GABA (inhibitory), Glycline (inhibitory or excitatory)

56
Q

Cholinergic receptors

A

Nicotinic, muscarinic

57
Q

Nicotinic receptors

A

Found on skeletal muscle in CNS and PNS, channels for Na+ and K+

58
Q

Muscarinic receptors

A

CNS and PNS, linked to G proteins, tissue response varies with receptor subtype

59
Q

Adrenergic receptors

A

Two classes (alpha, beta), linked to G proteins

60
Q

Slow neurocrine response

A

G-coupled protein pathway, uses messengers

61
Q

Fast neurocrine response

A

Gated ion channel pathway, direct effect

62
Q

Fate of neurotransmitters

A

Returned to axon terminals, transported into glial cells, inactivated by enzymes, diffuse out of synaptic cleft (into bloodstream)

63
Q

Divergent integration pathway

A

One neuron passes a signal to multiple targets

64
Q

Convergent integration pathway

A

Multiple neurons pass a signal to one target

65
Q

Inhibitory post-synaptic potential

A

Neurotransmitter release results in a hyperpolarization (more negative) of the post-synaptic membrane

66
Q

Excitatory post-synaptic potential

A

Neurotransmitter release results in a depolarization (more positive) of the post-synaptic membrane

67
Q

Summation of EPSPs and IPSPs

A

Net sum of all signals reaches the trigger zone and can either trigger an action potential or not

Integrative Physiology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions