Ch 7: Nervous Tissue

Question 1

What are the 3 functions of the nervous system?

Answer 1

Sensory (sense changes through sensory receptors)
Integrative (analyze incoming sensory info, make decisions regarding appropriate behaviors)
Motor (respond to stimuli)

Question 2

What is the order things go through?

Answer 2

Sensory Receptor —— (through sensory input) —– Integration —— (brain and spinal cord) —— (through motor input) —– Effector

Question 3

What are the 2 types of Motor Inputs?

Answer 3

Somatic and autonomic

Question 4

Which input is afferent?

Answer 4

Sensory

Question 5

Which input is efferent?

Answer 5

Motor

Question 6

Where are most neuron cell bodies located in?

Answer 6

The CNS

Question 7

What do dendrites do?

Answer 7

They receive information

Question 8

What do axons do?

Answer 8

Send information through the action potential

Question 9

What is the PNS?

Answer 9

Peripheral nervous system
(nerves come out of spinal cord and brain)

Question 10

What is the CNS?

Answer 10

Central nervous system
(spinal cord and brain)

Question 11

What is neuroglia?

Answer 11

Not electrically excitable
Make up about half the volume of the nervous system
can multiply and divide

Question 12

What wraps around the axon?

Answer 12

Myelin Sheath

Question 13

Where does the Schwann cells live?

Answer 13

in the PNS

Question 14

Where does the oligodendrocytes live?

Answer 14

in the CNS

Question 15

What are the 2 types of potentials?

Answer 15

Action Potential
Graded Potential

Question 16

Which potential can communicate over short and long distances?

Answer 16

Action Potential

Question 17

Which potential can communicate over short distances only?

Answer 17

Graded Potential

Question 18

Production of an AP or a GP depends on:

Answer 18

Existence of a resting membrane potential
Existence of certain ions channel

Question 19

What do Ligand-Gated channels respond to?

Answer 19

Chemical stimuli (ligand binds to receptor)

Question 20

What do Voltage-Gated channels respond to?

Answer 20

Direct changes in membrane potential (voltage)

Question 21

What can a voltmeter measure?

Answer 21

Potential (charge) difference across membrane of resting cell

Question 22

Resting membrane potential of a resting neuron is approx what?

Answer 22

70 mV

Question 23

What side of membrane is negatively charged relative to outside?

Answer 23

Cutoplasmic

Question 24

Potential is generated by what?

Answer 24

Differences in ionic composition of ICF and EFC
Na+ / K+ pump

Question 25

What is depolarization?

Answer 25

Decrease in membrane potential
Moves to 0 and above

Question 26

What is Hyperpolarization?

Answer 26

Increase in membrane potential
Away from 0

Question 27

Changes in Membrane Potential produce what 2 types of signals?

Answer 27

Graded potential
Action Potential

Question 28

Where does Action Potential occur?

Answer 28

IN muscle cells and axons of neurons

Question 29

For an axon to “fire”, what needs to happen?

Answer 29

Depolarization must reach threshold voltage to trigger AP

Question 30

What is All-Or-Nothing when it comes to AP?

Answer 30

An AP either happens completely or doesn’t happen at all

Question 31

AP graph

Answer 31

SEE THE NOTES

Question 32

Does AP die out?

Answer 32

No it self propagates

Question 33

What is the Presynaptic neuron?

Answer 33

Neuron conducting impulses toward synapses (sends info)

Question 34

What is the Postsynaptic neuron?

Answer 34

Cell transmitting electrical signal away from synapse
Receives info
May be another neuron, muscle fiber, or gland cell

Question 35

What are the 3 ways the Neurotransmitter can be removed from the synaptic cleft?

Answer 35

1. Diffusion
2. Enzymatic degradation
3. Re-Uptake into Axon terminal

Question 36

What are reflexes?

Answer 36

Rapid, predictable, and involuntary responses to stimuli

Question 37

Reflexes occur over neuron pathways called what?

Answer 37

Reflex Arcs