Chapter 11 Pt 2

What is a refractory period?

period during AP when another stimulus of normal strength will not cause a second AP

When does the absolute refractory period occur?

during depolarization and the first part of repolarization

When does the relative refractory period occur?

the end of absolute refractory period until RMP is re-established

What are the two types of synapses in the Nervous System?

electrical and chemical synapses

What does the presynaptic terminal do?

releases neurotransmitter

What does the postsynaptic terminal do?

receives neurotransmitter

What are the events at a Cholinergic Synapse?

1. an action potential arrives and depolarizes the synaptic terminal

2. action potential opens voltage gated Ca+ channels

3. extracellular Ca+ enters the synaptic terminal, triggering the exocytosis of ACh

4. ACh binds to receptors and depolarized the postsynaptic membrane

5. ACh is removed by the enzyme AChE

What are the steps to remove a neurotransmitter?

1. diffuse into ECF

2. enzymatically degraded

3. uptake by cells