Neurons

Question 1

What is a neuron?

Answer 1

• Transmit information

- Has dendrites, axons and axon terminal.

Question 2

What is in the soma?

Answer 2

Contains DNA

• Produces neurotransmitter
• If damaged, results in neuron death

Question 3

What is a Dendrite?

Answer 3

Main input sites for the cell (multibranched)

-The number of dendrites and their spines increases when learning occurs = Dendrite arborization

Question 4

What is an Axon?

Answer 4

Can be myelinated or unmyelinated

• Main axon usually has branches called collaterals
• Allows for communication with multiple cells

Question 5

What is an axon terminal?

Answer 5

Is found at the end of each axon.

-Release neurotransmitters into the synaptic cleft

Question 6

What is axoplasmic transport?

Answer 6

Movement of substances from/to soma to/from the peripheral ending
-Two types: anterograde, retrograde

Question 7

Anterograde transport?

Answer 7

movement of a substance away from the soma toward the peripheral ending.

Question 8

Retrograde transport?

Answer 8

Movement of a substance toward the soma from the peripheral ending.

Question 9

What happens to axonal transport with age?

Answer 9

Slows down

Question 10

What happens to axon terminals with learning?

Answer 10

increases

Question 11

Fact about axon terminal?

Answer 11

In addition to releasing neurotransmitter into the synaptic cleft, also reabsorb and reassemble parts of some neurotransmitters.

Question 12

Unipolar neuron

Answer 12

A single process (single axon) - usually interneurons CNS

-Not very many

Question 13

Pseudounipolar

Answer 13

Somatosensory neurons

• Sensation = skeleton, muscle, joints, skin (temp, pain, touch, proprioception.
• Soma is elevated off the processes
• Peripheral process between receptor cells and soma
• Central process soma to CNS
• Receptor endings converge onto peripheral process
• Convey sensory information
• Some special sensory toward CNS

Question 14

Bipolar

Answer 14

Two primary processes with soma in the middle

• 1 dendrite and 1 axon
• Some special sensory
• Found in retinal cells, CN I Olfactory cells, and CN VIII Vestibulocochlear cells (head, hearing, equilibrium

Question 15

Multipolar

Answer 15

Multiple dendrites arising from many parts of the soma.
Single axon (arises from the axon hillock)
-Voluntary motor neurons and many interneurons are multipolar 
-Most common neuron type in humans

Question 16

What neurons lack myelin?

Answer 16

Gray matter surface of the brain

Question 17

Can mature neurons reproduce?

Answer 17

No