Neuronal Signalling

Question 1

Excitable cells have

Answer 1

Voltage across membranes

Question 2

The cell membrane is selectively

Answer 2

Permeable

Question 3

Because the Cell membrane is selectively permeable this means ions need

Answer 3

Ion channels, they have specific channels for specific ions

Question 4

What is the resting potential of a cell

Answer 4

-70 to -90 mv

Question 5

What Ion is higher outside the cell

Answer 5

Sodium

Question 6

What ion is higher inside the cell

Answer 6

Potassium

Question 7

What is sodium is preferred equilibrium potential

Answer 7

+60 mv

Question 8

What is potassiums preferred equilibrium potential

Answer 8

-90mv

Question 9

What is calciums preferred equilibrium potential

Answer 9

+123mv

Question 10

What is chlorine preferred equilibrium potential

Answer 10

-40 MV

Question 11

What happens to the preferred equilibrium potential if too ion channels are open

Answer 11

Then the middle ground of the ions is found

Question 12

What is the resting membrane potential for neurons

Answer 12

-90 mv

Question 13

Why does action potentials occur

Answer 13

Due to rapid changes in membrane potential

Question 14

Stages of action potential

Answer 14

Resting stage
Stimulus 
Depolarisation 
Action potential 
Repolarisation 
Refractory period (hyperpolerisation)
Resting state

Question 15

What happens in depolarisation

Answer 15

Inside of the cell becomes less -

Question 16

What happens when delayed rectifier K+ channels open

Answer 16

Increase in K+ and decrease in Na+ permeability so membrane potential becomes less negative

Question 17

The synapse has gap

Answer 17

Junctions for electrical communication

Question 18

Neurotransmitters are released by a

Answer 18

Neuron

Question 19

+ synthesis occurs in the

Answer 19

Soma or axon terminal

Question 20

+ synthasis if s transported into

Answer 20

A vesicle for storage

Question 21

What is signal termination

Answer 21

The removal of neurotransmitter or degraded by an enzyme

Question 22

Signal termination prevents the signal from

Answer 22

Constantly being sent