Chapter 12 - Neuron & Glia Flashcards

1
Q

Excitibality

A
  • Neurons & Muscle cells are excitable
  • Ions move and changes in membrane potential conduct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Central Nervous System

A

Brain and Spinal Cord

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

Peripheral Nervous System

A

Nerves and Ganglia

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

Efference

A

Motor

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

Afference

A

Sensory

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

Tract

A

Bundle of axons
(CNS)

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

nucleus

A

group of cell bodies
(CNS)

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

nerve

A

bundle of axons (PNS)

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

ganglion

A

group of cell bodes (PNS)

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

Which glial cell type does the most different kinds of activities to support neurons?

A

Astrocytes

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

Schwann cells

A

wrap unmyelinated axons, but not multiple spiral wraps.

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

Ependymal cell

A
  • Produce CSF
  • Line the ventricles of the brain and central canal of the spinal cord and
  • Tufts of ependymal cell tissue = choroid plexus.
  • Creates barrier between these CSF filled spaces and the neural tissue.
  • Source of neural stem cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Choroid plexus

A

transport ions and nutrients from the blood into the cerebrospinal fluid.

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

Astrocyte

A

Regulate the ECF of neurons in the CNS:
Take up excess K+ to help neurons maintain their resting potential, “K+ sponges”
Take up excess neurotransmitter, prevent excess synaptic signalling, “NT sponges”.
Produce growth factors for neurons “nourish” and provide nutrition (fuel to make ATP).
Structural support:
Spatial support, “hold neurons in place” so they can maintain synapses
Guide migrating neurons during devel of brain
Cover brain surface
Cover nonsynaptic regions of neurons
Induce blood-brain-barrier to form.
Communicate electrically with neurons/influence synapses.
Form scar tissue after damage to the CNS.
Source of neural stem cells.

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

Microglia

A

Phagocytes
Scavengers of dead tissue (after injury to CNS)
Immune function against pathogens
Derived from Monocyte (white blood cell made in bone marrow)

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

oligodendrocytes

A

Myelinating cells of the CNS.

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

Resting Membrane potential

A

At Rest (unstimulated),A Neuron has a voltage

18
Q

Initial Stimulation

A

the act of disturbing a neuron that was at rest
- Can be accomplished 3 ways: electrically, chemically or physically

19
Q

Chemical Stimulation

A

Chemical (neurotransmitter, NT) binds to a receptor (ligand-gated channel shown) which allows for opening of an ion gate
and that changes the voltage

20
Q

Resting membrane potential

A

-70, potassium would need to leave the cell and take its positive charge outside the cell so it becomes more negative.

21
Q

threshold

A

-55, mV value at which the voltage gates will open

22
Q

+35

A

peak of action potential

23
Q

+62, ENa+

A

equilibrium potential for sodium
- sodium wants to bring as much positive charge as possible
- Sodium would want to bring in as many sodium ions as possible, to get the -70 mV all the way up to +62 mV

24
Q

-90, Ek+

A
  • Potassium balance is at -90
25
Depolarization
- brings cell closer to threshold later, EPSP - Moving in the positive direction of our resting potential - When sodium channels open
26
Hyperpolarization
- Brings cell away, more negative - this is inhibitory, brings cell away from threshold later, IPSP - When potassium channels open
27
At threshold
Voltage gated channels open
28
Repolarization
going back to its resting membrance potential
29
Absolute refactory period
wouldn't get another action potential at all
30
Relative action potential
if we have a big enough stimulus we can stimulate another action potential with that voltage gated sodium channel
31
what is undirectional conducation
one way, can't back up
32
Why does conduction occur
because of the refactory period
33
Saltatory conduction
jumps
34
Electrical synapses
rare in CNS but common in muscle. They make use of Gap Junction Proteins
35
Chemical Synapses
MUCH more prevalent – Adjustable! When Action Potential reaches Axon Terminal it stimulates Voltage-gated Ca++ channels The influx of Ca++ causes exocytosis of vesicles that contain Neurotransmitter (NT) Transmitter binds to a receptor on the mb of the next neuron (or muscle cell, etc.) There are 2 Different types of Receptors: Receptors associated w/ Ion Channels vs Receptors associated w/ 2nd Messenger Systems There are over 100 different types of transmitters. The text gives three examples: Acetylcholine, GABA, & Norepinephrine
36
Acetylcholine
will bind to a receptor that is connected to a Na+ channel. It lets Na+ enter to stimulate the postsynaptic neuron… an Excitatory Postsynaptic Potential (EPSP) which is a form of initial stimulation.
37
Neuromodulators
peptides released like small simple amino acid derived neurotransmitters, but they alter synapses.
38
Memory
due to “strengthened” synapses, when you form memorys its due to new synaptic connections
39
Temporal summation
Done in a timing kind of manner
40
Spatial summation
over space and area we're looking at we see three separate inputs to one post - synaptic neuron.
41
anasthesia
makes it impossible for pain stimulus to transmit afferently, don't sense pain because voltage gate channels are inhibited
42