Exam 2 - Lecture 24 (Synapse 2) Flashcards Preview

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Flashcards in Exam 2 - Lecture 24 (Synapse 2) Deck (14)
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1
Q

What are the 4 synaptic events that occur?

A
  1. APs open VG Ca2+ channels
  2. NTM release
  3. NMTs bind to their receptors
  4. Changes postsynaptic membrane potential
2
Q

What happens to postsynaptic membrane potential when NTMs bind to their receptors?

A

it changes

3
Q

What does each synaptic site generate?

A

postsynaptic membrane potentials

4
Q

What 5 things happen after an excitatory synapse?

A
  1. Excitatory NTMs are released (ACh or glutamate)
  2. ACh and Glutamate bind to AChR and GluR
  3. Rs open ligand-gated ion channels for Na+
  4. Na+ influx into postsyn. membrane
  5. Generates depolarizing EPSP
5
Q

What 5 things things after an inhibitory synapse?

A
  1. Inhibitory NTMs are released (glycine or GABA)
  2. Glycine and GABA bind to GlyR or GABA receptor
  3. Rs open ligand-gated Cl- channels
  4. Cl- influx
  5. Generates hyperpolarizing IPSP
6
Q

What happens when excitatory and inhibitory synapses act at the same time?

A

They cancel each other out

7
Q

Where do graded potentials travel?

A

To the axon hillock

8
Q

What is present at the axon hillock and axon?

A

VG Na+ and K+ channels

9
Q

When does the axon hillock generate APs?

A

When the sum of EPSPs and IPSPs goes over threshold membrane potential

10
Q

Why are EPSPs and IPSPs referred to as graded potentials?

A

Because they vary in size as opposed to being all or none

11
Q

What is spatial summation?

A

Summation of multiple separate signals arriving at different synaptic sites simultaneously (A+B; A+B+C)

12
Q

What is temporal summation?

A

Summation of multiple signals arriving at a single synaptic site (AA; BBB; CCCC)

13
Q

Where does the summed graded potential have to go over threshold voltage for an AP to occur?

A

at the axon hillock

14
Q

What is the role of EPSPs and IPSPs in tetanus?

A

EPSPs are present with no IPSPs so neurons are constantly firing.