Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

A/P > Lecture 7; 9/11 > Flashcards

Lecture 7; 9/11 Flashcards

Test 2

1
Q

What is sub-threshold?

A

Below the threshold required to have an AP

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

What is acute sub threshold potentials?

A

Weak stimulus/depolarization

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

Define: Threshold

A

Bar the stimulus/depolarization has to get over to have AP

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

The higher the stimulus over the threshold =

A

The faster the AP (also means stronger stimulus)

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

T/F: Every cell’s threshold potential is about -65

A

F

Every cell’s threshold for an AP is different depending on the type of tissue

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

What happens if the stimulus barely crosses the threshold?

A

Delayed AP

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

What is L-Type?

A

V-G Ca++ channels

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

What do L-type channels do in the heart?

A

They open slowly after depolarization which results in the plateau

Ca++ floods into the heart causing depolarization and contraction of the myocardial.

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

What does the depolarization plateau tell you?

A

How well the heart is going to pump

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

How long should the depolarization plateau be?

A

About 0.5 seconds

Compared to the usual 1ms

This gives the heart muscle time to contract and pump blood

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

If we decrease Cl- in the nervous system what could happen?

A

Seizures

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

We want to keep the nervous system_____

A

hyperpolarized

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

IV Ca++ and Mg++ _______ neuronal and muscular cell electrical excitability

A

Decreases

“Calming effect”

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

Describe a Calcium

A

Double charged
Large and clunky
Huge concentration gradient
Hangs out by cell wall

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

What happens to Na+ and K+ when you give Ca++?

A

Ca++ will block the leaky Na+ channels because Ca++ wants to get into the cell real bad, but its too big to go through there.

ECF Na++ will increase

ECF K++ will decrease and ICF will increase

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

What does decreased levels of Ca++ in the blood do?

A

More Na++ going into the cell which will increase the V(rm) = more excitable cell

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

T/F: Calcium inhibits electrical activity of the cell

A

T

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

What happens if you increase your serum K+?

A

You decrease the concentration gradient
K+ will not leave as fast

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

Where are 2 places that AP happen?

A

Motor neuron
Skeletal muscle

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

Trousseau sign is caused by

A

Hypocalcemia

Spasms in wrist

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

Chvostek’s sign is caused by

A

Hypocalcemia

Spasms in face

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

What does tetany mean?

A

involuntary muscle spasms

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

You can give a _____ bolus for tissues that are too depolarized

A

Ca++/Mg++

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

T/F: V-G Na++ channels are clogged by Ca++

A

F

Only effects leaky channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Myelin Sheath is a ______ structure that helps send AP ________
Robust Quickly
26
How does the diameter of the nerve effect the rate of the AP?
Wider = Faster More narrow = more resistance = slower
27
What are the 3 things that affect the rate of an AP?
Length of nerve Diameter of nerve Presence of Myelin sheath
28
How does myelin effect rate of AP?
No myelin = slow More myelin = faster
29
How is myelin formed?
Schwann cell nucleus grows overtime and wraps around the neuron in a spiral As it spirals, the water is squeezed out and it becomes a good insulator.
30
What does a myelin sheath do?
-Prevents Na+ from being pumped back out during an AP by a Na/K pump -Allows faster conduction of AP
31
What is the Nodes of Ranvier?
High density area packed with Lots of fast Na+ channels, Na/K pump, and K+ channels
32
What is Saltatory conduction?
Jumping from 1 node of renvier to another to spread the AP
33
What is part of the CNS?
Brain, spinal cord, Cranial nerve 2 (optic nerve)
34
T/F: Myelin makes cells less prone to ischemia
T
35
T/F: Myelin adds protection from crush injuries
T
36
What cell is responsible at producing/maintaining myelin in the CNS?
Oligodendrocytes
37
What cell is responsible at producing/maintaining myelin in the PNS?
Schwann Cells
38
Oligodendrocytes are _____ at reproducing myelin
Bad
39
Oligodendrocytes and Schwann cells are ______ cells
Glial
40
At what age do you begin to lose myelin?
40
41
Myelinated neurons are _____
energy efficient
42
Myelinated cell require _____ anesthesia
More d/t fast Na+ channels density at the nodes of renvier
43
If myelin sheath is degraded, what will come back?
Na/K pumps
44
What happens to the stuff under the myelin sheath?
degraded
45
What diseases are associated with loss of myelin sheath?
MS, Optic Neuritis, Guillain-Barre
46
After covid, what disease did we see an increase in regarding loss of myelin sheath?
Gullian- Barre From covid infection, body generated antibodies that affected the nervous system
47
Explain whats going on in demyelinating diseases
Since the meylin is degraded or gone Na/K ATP pumps will regenerate This will make it almost impossible to generate an AP in that area but the Na+ will just get pumped right back out and we will not be able to excite the cell.
48
How does an electrical synapse gap junction work?
Simple diffusion ion channel
49
How many connexins make a connexon?
6
50
Explain cell signaling with electrical synapse gap junctions
fast way to get AP from 1 cell to another 1. 6 connexins from a connexon 2. 2 connexions connect to form an ion channel (conduits) that allows the passage of small ions 3. Gap junction is the area where the connexons meet **Ca++ can go through but its big and it doesnt go well**
51
What area has a decrease in Gap junctions to allow for delays?
Pacing area of the heart
52
Where are connexions located?
In the cell wall
53
Which is faster, a chemical or electrical synapse?
Electrical
54
Fiber classification A:
Heavily myelinated AP sent fastest
55
Fiber classification C:
No myelination
56
Fiber classification B:
Lightly myelinated
57
If information is need to be sent quickly, what class of fibers would it be sent on?
Class A
58
What class of fibers are motor neurons under?
Class A
59
What is another name for a cell body?
Soma
60
Describe a neuron structure
-Cell body -Dendrites -Axon - Axon Hillock
61
What is the cell body?
Mostly the decision maker Has lots of mitochondria charge -60
62
What are dendrites?
Receiving end Recieves info from descending pathways from brain or sensory info from dorsal horn talks to other neurons This end is stuck to the anterior horn on the grey matter of the spine Negatively charged
63
What is the Axon Hillock?
Has multiple inhibitory connections (GABA receptors which increase Cl permeability) Supresses overactivity of the CNS Most negatively charged
64
What is the Axon?
Area that AP is sent down Used for signaling Myelinated
65
Excitatory connections will make the dendrite area more _____
positive
66
Inhibitory connections will make the dendrite more_____
negative
67
Alcohol is a ______ antagonist. It can cause ________
GABA Seizures
68
What happens if you remove the inhibitory connections on the axon hillock?
Increase excitability in the nervous system ---> seizures
69
What are Glial cells? what are the 4 kind?
Supporting cells that can divid and replicate Astrocytes, Ependymal cells, oligodendrocytes, and microglia
70
What are Astrocytes?
Important in BBB helps maintain balance in CSF, electrolytes, and pH buffer connects with endothelial
71
What is ependymal cells?
Produces and moves CSF with cilia
72
What is Microglia?
Acts as immune system degrades dead cells and keeps the area around the CNS clean
73
What are Oligodendrocytes
Form myelin sheath in the CNS **Schwann cells in PNS**
74
What are the 3 different types of neurons?
Multipolar Bipolar Pseudounipolar
75
Describe Neuron: Multipolar
**Decision making** Cell body attached to dendrites Cell body at top Cell body sits on top of axon AP travels down axon
76
Describe Neuron: Bipolar
**Special sensory** Ex) Optic nerve Dendrites at the top Cell body in the middle myelinated axon between dendrites and cell body and cell body and bottom
77
Describe Neuron: Pseudouipolar
**Sensory** Cell body only there to support the structure Majority of sensory cells outside spinal cord Decisions made by sensors itself Feeds in through the posterior/dorsal horn in the grey matter of the spinal cord
78
What type of neuron is a motor neuron?
Multipolar
79

A/P (33 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions