Structure Of The Neuron

Question 1

What is called Soma?

Answer 1

The soma is the cell body containing the nucleus and much of the machinery that provides for the life processes of the cell.
It’s shape varies considerably in different kinds of neurons.

Question 2

What are Dendrites?

Answer 2

(Greek-Dendron = Tree)
Dendrites derive from the soma (cell body) and look like branches of a tree.

Dendrites are important receivers for neural messages which are transmitted across the synapse.

Question 3

What is the Axon?

Answer 3

The axon is a long slender tube and often covered by a myelin sheath.

The outer surface of the axon carries information from the soma to the terminal buttons.

Basic message of Axon carries action potentials (brief electric impulse, always same size and duration, comes likes dendrites in different shapes)

Question 4

What are Terminal Buttons?

Answer 4

At the end of the axon branches are little knobs called Terminal Buttons.

The terminal buttons house synaptic vesicles containing neurotransmitters.

The terminal buttons convert an electrical message into a chemical one by releasing the neurotransmitters when an action potential travelling down the axon reaches them.

Depending on whether the neurotransmitters are inhibitory or excitatory , they determine whether an action potential occurs in its axon.

Question 5

What are the four basic structures of the neuron?

Answer 5

The soma
The dendrites
The axon
The terminal buttons

Question 6

What kind of supporting cells are in the

Central Nervous System ?

Answer 6

Astrocytes
Oligodendrocytes
Microglia

Provide Myelin sheath &
Activate Immune responses.

Question 7

What kind of supporting cells are in the peripheral nervous system?

Answer 7

Schwann Cells

Provide Myelin &
Assist with neural regeneration.

Question 8

What is the blood-brain barrier?

Answer 8

The blood-brain barrier protects the Central Nervous system
(By selectively permitting only some substances to enter)

It is made of capillary walls and helps regulate the composition of fluids in the brain (protecting neuronal transmission).

The blood-brain barrier is more permeable in the area postrema, permitting Neurons in this region to detect the presence of toxic substances.