Neuron Structure

Question 1

What is a soma (cell body)?

Answer 1

Metabolic center of the cell

Contains nucleus and DNA

Question 2

What is a dendrite?

Answer 2

Extension of the cell body that is covered with thousands of synapses

It is the post synaptic membrane that has molecular RECEPTORS that detect neurotransmitters (from presynaptic membranes of other cells)

Covered with thousands of dendritic spines that inc the number of synapses able to connect with

Question 3

What is axon?

Answer 3

Projected from the cell body and used for projection of information over long distances

Question 4

What is another name for a presynaptic terminal?

Answer 4

Terminal bouton

Question 5

What is a terminal bouton?

Answer 5

This is the PRESYNAPTIC TERMINAL at the end of the axon that contains SYNAPTIC VESICLES that house NEUROTRANSMITTERS.

Here, info electrical impulses from
The axon are converted into a chemical signal (aka neurotransmitter)

Question 6

What is another name for a synapse?

Answer 6

SYNAPTIC cleft

Question 7

What is a synapse?

Answer 7

A synaptic cleft. It is the space between the axon/terminal bouton of THE presynaptic neuron and the dendrite of the postsynaptic neuron.

Here chemical information (neurotransmitters) cross from one neuron to the next:

Question 8

What do Olidodendroglial cells do?

Answer 8

They insulate axons with myelin sheaths (lipid/fat + protein substance)

Question 9

What are Node of Ranviers and what do they do?

Answer 9

Periodical interruptions of the myelin sheaths covering the axon.

They are used for SALTATORY CONDUCTION ( aka Hop conduction) of electrical impulses traveling down the axon which helps to speed the propagation (aka transmission)

Question 10

What is a graded potential?

Answer 10

This is the sum of inhibitory and excitation impulses sent from presynaptic neurons to the postsynaptic neuron. This affect whether the neuron will fire or not as related to the action potential.

Question 11

What is a action potential?

Answer 11

This is the CRITICAL THRESHOLD required for a neuron to fire.

According to the graded potential offered by the presynaptic neurotransmitters, if the threshold is met; the neuron will fire.

It is an all or nothing response (not related to the intensity of the fire)

Intensity is related to firing rate.