Neuronal Signaling

Question 1

Which part of the neuron takes input and responds with a graded potential?

Answer 1

Dendrites

Question 2

Which part of the neuron is the output process?

Answer 2

Axon

Question 3

What are found in the axon terminals?

Answer 3

Vesicles with neurotransmitters

Question 4

What part of the axon contains the nucleus?

Answer 4

Soma

Question 5

Do neurons divide?

Answer 5

No.

Except hippocampus!!

Question 6

What are the three classifications of neurons based on where the signal is traveling?

Answer 6

1. Afferent: PNS -> CNS
2. Interneurons: all w/in CNS
3. Efferent: CNS -> PNS

Question 7

______ neurons have cell bodies (ganglia) outside of the CNS.

Answer 7

Afferent

Question 8

____ cells make up 90% of the cells in the CNS.

Answer 8

Glial

Question 9

T/F: Glial cells undergo cell division.

Answer 9

TRUE

Question 10

_______ cells are types of glial cells found in the PNS.

Answer 10

Schwann

Question 11

What are the three types of glial cells in the CNS?

Answer 11

1. Oligodendrocytes: myelination
2. Microglia: phagocytic role
3. Astrocytes: buffering role in ECF

Question 12

Which glial cell makes up the blood brain barrier?

Answer 12

Astrocytes

Question 13

T/F: There is one Schwann cell per axon.

Answer 13

FALSE

Many Schwann cells/axon

Question 14

T/F: One oligodendrocyte contributes to many axons.

Answer 14

TRUE

Question 15

What two problems can cause peripheral demyelination?

Answer 15

1. Guillain-Barre sydrome

2. Nerve trauma

Question 16

T/F: Microglia are in a constant reactive state.

Answer 16

FALSE

Go from active to inactive states

Question 17

_______ are involved in “pruning” unused dendrites.

Answer 17

Microglia

Question 18

T/F: Neuron-glia interactions are done via a synapse.

Answer 18

FALSE

Direct contact

Question 19

What is axonal transport and what part of the neuron is responsible for these actions?

Answer 19

Movement of proteins around the neuron; microtubules

Question 20

_________ transport uses kinesins and moves proteins from cell body towards terminal.

Answer 20

Anterograde

Question 21

Which type of transport moves proteins towards the cell body and what motor protein is utilized?

Answer 21

Retrograde transport; dyneins

Question 22

What is a major concern with retrograde transport?

Answer 22

Brings viruses to nucleus

Question 23

T/F: Damaged CNS neurons do not regenerate.

Answer 23

TRUE

Question 24

What happens to a damaged CNS neuron?

Answer 24

The axons will not reach their target

Question 25

If a patient experiences nerve injury from oral surgery can they recover?

Answer 25

Yes depending on severity

Question 26

In a severe nerve injury the cell body will die. If less severe, the cell body will undergo what process?

Answer 26

Chromatolysis (swelling)

Question 27

When a neuron is injured it goes through what process of degeneration?

Answer 27

Anterograde degeneration

Question 28

Describe the process of nerve regeneration in the PNS.

Answer 28

1. Schwann cells produce laminin 2. Schwann cells secrete NGF which travels via retrograde transport 3. NGF regulates gene expression to promote sprouting

Question 29

What cell provides as a source for neuronal glucose?

Answer 29

Astrocyte

Question 30

When a neuron is severely injured it can undergo what type of degeneration?

Answer 30

Transynaptic degeneration

Question 31

What are the two classifications of synapses?

Answer 31

Chemical and Electrical (gap junction)

Question 32

What are the three types of chemical synapses?

Answer 32

1. Axo-somatic 2. Axo-dendritic 3. Axo-axonic

Question 33

Describe the actions at a synapse.

Answer 33

1. AP reaches axon terminal 2. V-gated Ca channels let in Ca 3. Vesicles release NTs into synapse 4. NT binds to postsynaptic receptors 5. NT is removed from synapse

Question 34

In what ways can drugs act on a synaptic junction?

Answer 34

1. Do a multitude of things to affect NT release, uptake, synthesis. 2. Block/stimulate postsynaptic receptor 3. Block/stimulate postsynaptic 2nd messenger

Question 35

_______ are released with NTs to modulate their activity.

Answer 35

Neuromodulators

Question 36

How is Acetylcholine controlled?

Answer 36

1. Diffusion and degradation by acetylcholinesterase | 2. Choline re-uptake by presynaptic neuron

Question 37

Give four examples of neurons that release ACh.

Answer 37

1. Motor neurons 2. Nucleus basalis and pons 3. Preganglionic symp. and psymp. 4. All postganglionic psymp.