Test One

Question 1

neurophysiology

Answer 1

the study of how the nervous system functions

Question 2

neuron

Answer 2

cell that does work in nervous system

Question 3

semi permeable

Answer 3

allows some ions to pass through and excludes other ions almost exclusively

Question 4

ION

Answer 4

single atoms of chemical elements which have too many or too few electrons

Question 5

action potential

Answer 5

basic mechanism by which neurons carry information over distances

Question 6

About how many neurons are estimated to be in the CNS?

Answer 6

10 billion

Question 7

what two main structures are neurons composed of?

Answer 7

cell body and neurites

Question 8

What are neurites made of?

Answer 8

dendrite and axon

Question 9

bipolar neurons are found where?

Answer 9

cochlear and retina

Question 10

dendrites conduct impulses ___ the soma

Answer 10

toward

Question 11

axons conduct impulses ___ from the soma

Answer 11

away

Question 12

Most common type of neuron

Answer 12

multipolar

Question 13

afferent conduct

Answer 13

toward

Question 14

efferent conduct

Answer 14

away

Question 15

what is the function of association neurons?

Answer 15

communication between neurons and conduct impulses

Question 16

another name for association neurons

Answer 16

internuncial neurons or interneurons

Question 17

resting membrane potential

Answer 17

electrical difference across cell membrane

Question 18

volt range of RMP

Answer 18

-60 to -80 mV

Question 19

active transport

Answer 19

process in which a cell membrane moves ions against a concentration gradient

Question 20

excitation threshold

Answer 20

cell membrane must be depolarized to a critical level to produce action potential

Question 21

all or nothing law

Answer 21

any threshold stimulus produces a full size action potential and a less than threshold stimulus produces no action potential

Question 22

conduction velocity affects

Answer 22

myelin and the diameter of the axon

Question 23

1 to 2 mm along its length interruption

Answer 23

node of Ranvier

Question 24

myelin sheath within

Answer 24

oligodendrocytes

Question 25

myelin sheath outside

Answer 25

schwann cells

Question 26

first suspected the electrical nature

Answer 26

Galvani

Question 27

propagation in relation to action potentials

Answer 27

signal goes cell to cell along nerve pathway

Question 28

absolute refractory period

Answer 28

when cell is firing (producing spike) cell unresponsive to stimulus

Question 29

relative refractory

Answer 29

during repolarization and hyperpolarization larger stimuls needed

Question 30

nobel prize 1963

Answer 30

Hodgkin and huxley

Question 31

irritable cells

Answer 31

capable of being stimulated