nervous system Flashcards

(38 cards)

1
Q

neurons

A

nerve cells that conduct signals, nucleated body, dendrites= nerves receptive apparatus, axon= long+carries away impulses, myelin= fatty sheath covered axon

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

central nervous system

A

brain + nerve cord= interneurons conduct impulses= 99% of all neurons

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

peripheral nervous system

A

afferent and efferent

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

afferent (sensory) neurons

A

conduct sensory info from body to CNS

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

efferent (motor) neurons

A

conduct motor info from CNS to the body

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

nerves

A

collections of axon bound together by connective tissue

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

ganglia

A

collections of neuronal cell bodies lying in the PNS

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

neuroglia

A

(glial=glue) non-nervous cell support neurons (keep glued together)

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

Schwann cells

A

forms myelin in the PNS

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

oligodendrocytes

A

forms the myelin in the CNS

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

nerve action potential

A

all nerve signals use electro-chemical message, relies on ion exchange across neuron membrane alter change inside cell

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

action potential

A

all or none phenom- either conducting signal or not

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

membrane potential

A

difference in electrical charge between inside/outside cell at rest neuron= more (-) than fluid

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

sodium-potassium pump

A

moves sodium and potassium in opp. directions against its concentration gradient (channels specific to either)
voltage gated= open v. closed depends on membrane potential

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

depolarization (rising phase)

A

Changes in membrane potential causes voltage-gated Na+ channels to open.
Na+ rush into the axon from the outside.
Interior becomes slightly positive with respect to exterior, membrane is depolarized.

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

repolarization

A

Na+ gates close.
K+ gates open and K+ ions move out.
Reestablishes the resting membrane potential.
Interior once again negative with respect to the exterior.
A new action potential cannot occur because the sodium is inside and the potassium is outside.
Sodium-potassium pump re-establishes the resting potential

17
Q

synapse

A

Junction between two neurons or a neuron and an effector (muscle or gland).
An action potential passing down an axon must cross a small gap, the synapse

18
Q

presynaptic knobs release neurotransmitters.

A

One of the most common is acetylcholine

19
Q

Neurotransmitters

A

Diffuse across the gap in a fraction of a millisecond.
Bind to receptor molecules on ion channels in the postsynaptic membrane.
Causes a voltage change in the postsynaptic membrane.

20
Q

conduction and myelination

A

Nodes of Ranvier are exposed areas of the axon between adjacent regions of myelin.
Myelin insulation prevents depolarization, which, therefore, only occurs at the nodes.
Increases the speed of conduction.

21
Q

saltatory conduction

A

describes jumping behavior of the action potential which leaps from node to node.

22
Q

bilateral nervous system

A

sponges lack nerves or true neural cell types
cnidaria have a nerve net
flatworms= simplest system

23
Q

nervous system of arthropods

A

annelids= advanced to segments ganglia ganglia are larger, better developed sense organs

24
Q

encephalization

A

Increase and elaboration in size of the brain.
The brain and spinal cord compose the central nervous system.

25
divisions of the vertebrate
forebrain (cerebrum +)- voluntary movement-touch smell Midbrain- information processing- vision hearing Hindbrain (Cerebellum +)- involuntary- HR, balance
26
cerebral cortex
is site of “higher” mental activities. Largest of vertebrates
27
corpus callosum
neural connection bridging the right and left hemispheres. left- language, math, learning right- spatial, musical, intuition
28
somatic nervous sytem
division of efferent division, conducts motor messages to skeletal muscles
29
autonomic nervous sytem
division of efferent system, controls involuntary internal functions, smooth muscle
30
sympathetic nervous system
division of autonomic nervous system, active under conditions of physical stress or maintaining homeostasis
31
parasympathetic
mostly active during rest periods
32
sense organs
afferent system, stimuli come as energy (electrical, mechanical, chemical, radiant)
33
exteroceptors
are located near the external body surface
34
proprioceptors
in muscles, tendons, and joints, detect changes in tension =
35
interoceptors
in internal organs
36
chemoreceptors
smell (olfaction) and taste
37
mechanoreceptors
touch, pressure, stretching, sound, vibrations, gravity, motion
38
photoreceptors
vision