Nerve conduction - Synapse (3)

Question 1

The type of affect NT has on postsynaptic membrane is determined by what?

Answer 1

The type of ion channels it opens

Question 2

9. The type of affect nt has on post sy membrane is determined by the type of ion channels it opens: Na+

Answer 2

• Na+ enters neuron and produces excitatory post synaptic potential (depolarization)

Question 3

9. The type of affect nt has on post sy membrane is determined by the type of ion channels it opens: K+

Answer 3

• K+ leaves the neuron and produces inhibitory post synaptic potential (hyperpolarization)

Question 4

9. The type of affect nt has on post sy membrane is determined by the type of ion channels it opens: Cl-

Answer 4

a. if neuron is at rest diffusion and electrostatic forces are balanced and there is no Cl- movement and thus has no affect
b. If neuron is firing, the outside of membrane will be negative and electrostatic force will cause Cl- to enter neuron and it will “neutralize” the EPSP by returning the membrane to resting potential and slow the rate of firing

Question 5

9. The type of affect nt has on post sy membrane is determined by the type of ion channels it opens: Ca+EPSP

Answer 5

a. causes release of ts in terminal button
b. binds with and activates enzymes that are involved in biochemical and structural changes in neurons important for processes such as learning

Question 6

What happens to postsynaptic potentials briefly after release?

Answer 6

TERMINATION!

Question 7

What is the most common form of NT deactivation?

Answer 7

• Reuptake most common form of nt deactivation – membrane contains transporter molecules that remove nt from cleft into cytoplasm

Question 8

How is acetylcholine (ach) deactivated?

Answer 8

• Ach is deactivated by enzyme present in cleft called acetylcholinesterase which divides Ach into constituent molecules