Bioelectricity, electrical signals, and neural communication

Question 1

resting potential

Answer 1

electrical potential difference that exists across the plasma membrane of every cell in the body

Question 2

Average resting potential of neuron

Answer 2

-70mV

Question 3

resting potential is a steady-state equlibrium that develops because

Answer 3

unequal distribution and permeability to key ions

Question 4

ICF

Answer 4

low Na+, high K+, low Cl- (slightly negative)

Question 5

ECF

Answer 5

high Na+, low K+, high Cl- (slightly positive)

Question 6

flux

Answer 6

moving something across a membrane

Question 7

transmembrane flux of an ion through an open ion channel is due to

Answer 7

electrochemical potential of that ion

Question 8

what causes unequal distribution of ions–leading to an electrochemical potential developing?

Answer 8

mostly caused by primary active transport–Na+/K+

Question 9

two influences on ions

Answer 9

electrical and chemical

Question 10

Nernst equilibrium potential (reversal potential)

Answer 10

the membrane potential that would bring about electrochemical equilibrium of a cell if it were only permeable to one ion species

Question 11

electrochemical equilibrium

Answer 11

steady-state condition in which there is NO NET ionic flux. the two driving forces, electrical and chemical, cancel each other out

Question 12

electromotive force is

Answer 12

equal in magnitude by opposite in direction of the diffusional force

Question 13

The nernst equation provides

Answer 13

boundaries. it gives you the extremes, and the cell will be somewhere between the extremes

Question 14

Equilibrium potential of K+

Answer 14

K+= -90mV

Question 15

Equilibrium potential of Na+

Answer 15

Na+ = +60mV

Question 16

eq potential of Ca2+

Answer 16

Ca2+ = +130mV

Question 17

eq potential of Cl-

Answer 17

Cl- = -86mV

Question 18

under normal resting conditions, the membrane is about 30x more permeable to ___ than ___

Answer 18

K+ (-90mV) than Na+ (+60mV)

Question 19

Vm=resting potential of the cell

Answer 19

Vm= -70mV

Question 20

more permeable a cell is to a particular ion

Answer 20

the more influence the ion has on resting potential–K+ has a much bigger influence on resting potential than Na+

Question 21

Goldman Eqn

Answer 21

resting membrane potential–steady-state condition in which there is not net ionic flux. Accounts for the permeability of ALL relevant ion species

Question 22

Excitable cells

Answer 22

utilize electrical signals to integrate and transmit information

Question 23

graded potentials

Answer 23

local and non-propagated electrical signals

Question 24

action potentials

Answer 24

self-propagating electrical signals

Question 25

depolarization

Answer 25

upshoot, more positive than resting

Question 26

repolarization

Answer 26

going back towards resting

Question 27

hyperpolarization

Answer 27

more negative than resting (refractory period)

Question 28

receptive segment of neuron

Answer 28

where stimulus input is recieved and transduced into local graded potentials