Exam 3 review

Question 1

Define: responsiveness, conductivity, contractility, extensibility and elasticity. why are they signiificant?

Answer 1

begin e- signals. wave of e- signals. pull to create movement. stretch between contractions. recoil to beginning.

Question 2

Define Nerve and Ganglion in PNS

Answer 2

Nerve: collection of nerve fibers (axons) Ganglion: collection of nerve bodies

Question 3

what is the difference between the visceral and somatic divisions of the Sensory and Motor systems?

Answer 3

Visceral-Sensory: signals from viscera to brain. Visceral-Motor: signals from brain to viscera. Somatic Sensory: signals from skin, muscle, bone and joints to brain. Somatic-Motor: signals from brain to skin, muscle, bone and joint.

Question 4

what is another name for visceral motor division? how is it divided?

Answer 4

ANS: sympathetic (fight or flight) parasympathetic (rest and digest)

Question 5

Physiological characteristics of nerve cell (neuron)

Answer 5

excitability, conductivity and secretion

Question 6

when a signal travels through the body, it travels through what THREE neurons?

Answer 6

sensory, inter- and motor

Question 7

diameters of axons and somas

Answer 7

axons: 1-20 micrometers. Somas: 5-135 micrometers

Question 8

fxn of nueroglia “oligodendrocytes”

Answer 8

myelinate axons only in CNS

Question 9

fxn of ependymal cells

Answer 9

create CSF, appear to be epithelial cells only in CNF

Question 10

fxn of microglia

Answer 10

only in CNF check brain tissue and consume foreign matter

Question 11

fxn of astrocytes

Answer 11

Only in CNF many fxns of not already stated they do it

Question 12

fxn of schwann cells

Answer 12

Only in PNS myelinate axons and regenerate nerve growth

Question 13

fxn of satellite cells

Answer 13

provide e- insulation around somas

Question 14

why are schwann cells and oligodendricytes necessary?

Answer 14

to increase rate of axn pot.

Question 15

significance of Rita Levi-Montalcini

Answer 15

discovered Nerve Growth Factor which prevents apoptosis of growing nerves

Question 16

GABA-ergic synapse

Answer 16

GABA is a NT that binds to ion channels (prompting changes in membrane potential) however, stimulates Cl- which LOWERS membrane potential. Inhibiting its ability to fire.

Question 17

Cholinergic synapse

Answer 17

excitatory synapse using ACh as NT.

Question 18

when Ulric decreases his appetite he is + what NT?

Answer 18

cholecystokin

Question 19

when Ulric increases his endurance he is + what NT?

Answer 19

Beta-endorphin.

Question 20

when feeling depressed, Ulric elevates his mood by + NT?

Answer 20

Dopamine

Question 21

Ulric has a hard time controlling this homeostatic NT and this NT released by mast cells and basophiles

Answer 21

Serotonin and histamines

Question 22

4 characteristics of Local potential

Answer 22

1. graded 2. decremental- get weaker 3. reversible 4. either excitatory or inhibitory

Question 23

what causes K+ to diffuse out of a resting cell? what attracts it into the cell?

Answer 23

K+ open more slowly than Na+. once rising pot hits peak K+ are repulsed by positive ICF and diffuse out.

Question 24

what happens to Na+ when a neuron is +, why does movement of Na+ raise the voltage?

Answer 24

when neuron is + Na floods into cell quickly and increase in Na+ increases voltage

Question 25

what makes and axn potential rasie to +35 mV? what makes it drop again?

Answer 25

increase of Na+. K+ leaving cell

Question 26

what is RMP and what causes e- impulses in body?

Answer 26

resting membrane potential is -70mV and e- impulses are caused by the movement of Na+ and K+ through gated channels in plasma membrane

Question 27

an example of IPSP is?

Answer 27

GABA ergic responces

Question 28

an example of EPSP is?

Answer 28

Cholinergic synapses.

Question 29

Temporal summation

Answer 29

one presynaptic neuron +ing quickly enough to induce a rxn

Question 30

Spatial summation

Answer 30

several synapses add up to threshold at axon hillock