Nervous system 3

Question 1

how do nerve cells communicate

Answer 1

electrical signals

Question 2

name for electrical charge at rest and figure

Answer 2

resting membrane potential - 70mV, negative inside of cell is negative compared to outside

Question 3

why is inside of cell more negative than outside?

Answer 3

> lots of big negativly charged molecules inside cell that are trapped
action of soduim potassium pump ( 3 Na+ out and 2+ in )
action of ion channel - structures in the membrane which only specific ions can pass through e.g. sodium channel for Na+

Question 4

4 diff types of channels

Answer 4

ungated channels ( K+, leak out of cell)
gated channels ; (Na+, at rest = closed)
Chemically-gated Channels
electrically-gated channels 
mechanically-gated channels

Question 5

what does nerve cell need to become active

Answer 5

needs to receive sufficient stimulation ( e.g. nuerotransmitters ) from other nerve cells

Question 6

min amount of stimulation needed to activate cell

Answer 6

Threshold

Question 7

what generally happens once reached enough stimulation

Answer 7

all-or-none law - once threshold reached will activate ( quantity doesn’t matter / on/off)

Question 8

change in electrical impulse

Answer 8

action potential