Anatomy of a synapse

Question 1

What did Santiago Ramon y Cajal do?

Answer 1

He made drawings looking at the nervous system. He drew neurons, cell bodies, axons, and astrocytes. He also came up with the idea of synapses

Question 2

Desribe the structure of a typical neuron

Answer 2

a typical neuron has soma (cell body) this is where the nucleus is located. Nerve fibers that are capable of rapidly conducting impulses away from the cell body

Question 3

describe the soma

Answer 3

The bulbous end of a neuron, contaning the cell nucleus

Question 4

Describe an axon

Answer 4

nerve fibers that are capable of rapidly conducting impulses away fro the neuron cell body.

Question 5

Describe dentrites

Answer 5

A long, branch outgrowth or extension from a neuron that carries electrical signals from synapses to the cell body.

Question 6

what is the presynaptic terminal?

Answer 6

A specialized area within the axon of the presynaptic cell that contians neurotransmitters enclosed in synaptic vesicles.

Question 7

How does communication between neurons occur?

Answer 7

Communication between neurons occurs at the synapses. Synapses are specialized junctions. Excitatory messages cause the next cell to “fire” - and continue to carry the action potential.

Question 8

What are the types of synpases?

Answer 8

Electrical and chemical synapses

Question 9

Describe electrical synapses

Answer 9

Electrical transmission is mediated between neurons by clusters of intercellular channels called gap junctions. They see very rapid transmission. Electrical synapses are bidirectional as the current can flow between two neurons at these electrical synapses.

Question 10

Describe Chemical synapses

Answer 10

• More common in the NS.

Question 11

Synpatic vesicle cycle

Answer 11

• We have synaptic vesicles that have to be docked at active zones; this docking requires a number of proteins

Question 12

Proteins are important for _______________________________________

Answer 12

Synaptic Vesicle cycles

Question 13

Describe neurotransmitters

Answer 13

• Chemical messengers that transmit info between neurons

Question 14

Glia ________around the cell

Answer 14

wraps

Question 15

What are the different types of glia ?

Answer 15

Astrocytes

Question 16

Astrocytes

Answer 16

• Found in the CNS

Question 17

Oligodendrocytes

Answer 17

• Found in the CNS

Question 18

Microglia

Answer 18

•Found in the CNS

Question 19

Schwann cells

Answer 19

• Found in the PNS

Question 20

Describe how astrocytes detect and control synaptic transmission

Answer 20

• Astrocytes are in close contact with neurons

Question 21

Describe Synapses

Answer 21

specialized structures where nerve cells communicate with each other through a process called synaptic transmission.

Question 22

Why are synapses important?

Answer 22

• Synapses are functional units of the brain and are targets of many diseases and drugs.

Question 23

Active zones

Answer 23

are sites where synaptic vesislces exocytosis and fusion occurs

Question 24

Periactive zone

Answer 24

are sites where synaptic vesicles endocytsis occurs

Question 25

what are the functions that active zones perform in neurotransitter release ?

Answer 25

1. They dock and prime synaptic vesicles

Question 26

Describe the postsynaptic density

Answer 26

• PSD is a protein-dense specialization attached to the postsynaptic membrane

Question 27

Descirbe the 4 different active zones

Answer 27

1. Dense projections: neuromuscular junction C.elegans

Question 28

Cytoskeletal matrix assembled at Active zones (CAZ)

Answer 28

The CAZ is a proteinaceous cytomatrix that serves as an organizational platform for proteins involved in synapse assembly and regulation

Question 29

How can syanpses differ in relase probabilities?

Answer 29

Not all synapses are the same. They can differ in release probabilities, this is true across and within species.

Question 30

Name 6 reasons why synapses can differ in their release probabilities

Answer 30

1. Active zones per synapse. More active zones lead to more neurotransmitter release.

Question 31

Some proteins found at Active zones are

Answer 31

SNARE proteins

Question 32

Domains of proteins allow them to __________________________

Answer 32

interact with each other

Question 33

describe RIM

Answer 33

• RIM binds to a synaptic vesicle called Rab3

Question 34

What happens without RIM and RIM BP

Answer 34

the Ca2+ channels are no longer in close proximity to these synaptic vesicles and the recruitment of Ca2+ channels reduces the amount of neurotransmitter release.

Question 35

describe ELKs

Answer 35

• ELKs regulate Ca2+ influx and neurotransmitter release

Question 36

Describe Liprin

Answer 36

• Liprin plays key roles in AZ formation and synaptic vesicle accumulation

Question 37

Describe Munc-13

Answer 37

• Munc-13 is an AZ protein that is essential for syanptic vesicle priming.