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Flashcards in Nerves 5 Deck (20):
1

What does the action potential in the presynaptic terminal cause in the NMJ?

- Voltage gated calcium channels open and calcium enters the cell

2

What does the calcium in the pre synaptic terminal cause?

- Allow vesicles containing neurotransmitters to be exocytosed

3

What is the neurotransmitter that is released at the NMJ?

- ACh

4

What does the ACh at the synapse do?

- Diffuses across
- Binds to nicotinic receptors

5

What does the binding to the nicotinic receptors do?

- Opens ligand gated Na/K channels
- Evokes a local potential

6

What is the local potential of the NMJ called?

End plate

7

What does the end plate potential always do?

- ALWAYS triggers an AP

8

How is ACh removed from the synapse?

- Acetylcholinesterase
- Choline groups are reuptaken

9

What does tetrodotoxin do?

Blocks sodium channels so AP's can't be generated

10

What does joro spider toxin do?

Blocks calcium channels so calcium dependent exocytosis of ACh can't occur

11

What does botulinum toxin do?

- Prevents vesicle fusion

12

What does curare do?

Blocks ACh receptors

13

What do anticholinesterases do?

- Prevent the action of acetylcholinesterase
- Increase time that ACh is in the synaptic cleft

14

4 qualities of the CNS synapses that make them more complex than the NMJ?

- Multiple neurotransmitters
- Complex connectivity
- Different postsynaptic potentials
- Many different anatomical arrangement of synapses

15

What does the range of post synaptic potentials in the CNS allow?

Complex synaptic integration

16

What 3 anatomical arrangements can synapses in the CNS have?

- Axo somatic
- Axo dendritic
- Axo axonal

17

Axo somatic?

Synapses with the soma

18

Axo dendritic?

Synapses with the dendrite

19

Axo axonal?

Synapses with the initial segment

20

What is meant by synaptic connectivity in the CNS?

Can be
- Converging
- Diverging
Increases the complexity