Nervous System Section 1

Question 1

What is a Neuron

Answer 1

A specialized cell that converts electrochemical pulses throughout the body

Question 2

How many types of neurons are there ?

Answer 2

4

Question 3

How many parts does a neuron consist of ?

Answer 3

Three parts the soma, dendrites and axons.

Question 4

What is the difference between dendrites and axons?

Answer 4

The dendrites receive information while the axons transfer information.

Question 5

What is another name for the cell body of a neuron ?

Answer 5

Perikaryon

Question 6

Is it true that axons are longer ?

Answer 6

Yes they project longer

Question 7

What is Myelin

Answer 7

Myelin is a insulating sheath that surrounds the axons.

Question 8

What are the roles of the nervous system ?

Answer 8

Sensory input, Integration and motor output

Question 9

What is the structural classification of the nervous system ?

Answer 9

The central nervous system and the peripheral nervous system

Question 10

What is the difference between neurons and Neuroglia

Answer 10

Neurons don’t divide Neuroglia do

Question 11

What are the types of neurons

Answer 11

Unipolar, Bipolar, Psuedopolar and Multipolar

Question 12

What is synapse

Answer 12

A synapse is a junction between neurons

Question 13

What do axons end in ?

Answer 13

Terminals

Question 14

What is synaptic cleft ?

Answer 14

A synaptic cleft is a gap between adjacent neurons

Question 15

What is a nerve impulse

Answer 15

A nerve impulse is a electric signal produced when a neuron is stimulated

Question 16

Does Myelin increase nerve impulse propagation ?

Answer 16

Myelin does increase nerve impulse propagation

Question 17

What are the ions needed for life

Answer 17

Sodium, Chloride, Potassium , Magnesium and calcium.

Question 18

What is an action potential

Answer 18

An action potential is when a neural impulse fires.

Question 19

What is threshold ?

Answer 19

Threshold is what triggers action potential

Question 20

What is diffusion

Answer 20

Diffusion is the movement of molecules from an area of high concentration to low concentration

Question 21

How many types of summation is there ?

Answer 21

Two types

Question 22

What are the two types of summation ?

Answer 22

Temporal and Spatial

Question 23

Action Potential pt 1

Answer 23

The stimulus causes sodium channels to open allowing the Na+ ions that were outside the membrane to rush into the cell

Question 24

Why are sodium channels called gated ion channels.

Answer 24

Sodium Channels are called gated ion channels because they open and close in response to signals like ( electrical charges) . When the Na+ ions enter the neuron the cell’s electrical potential becomes more positive

Question 25

Action Potential Pt 2:

Answer 25

If the signal is strong enough and the voltage reaches threshold it triggers action potential .It requires -55 millivolts

Question 26

Remember

Answer 26

The more gated the ion channels are open. The more Na+ ions inside the cell which depolarizes so that the charges across the membrane completely reverse. The inside becomes + while the outside is negative.