Neurons

Question 1

Neuron diagram

Answer 1

Question 2

What is a neuron?

Answer 2

The basic building blocks of the nervous system, neurons are nerve cells that process and transmit messages through electrical and chemical
signals. They provide the nervous system with its primary means of communication.
There are 100 billion neurons in the human nervous system 80% located in the brain

Question 3

Sensory neurons

Answer 3

They carry messages from the PNS to the CNS.They have long dendrites and short axons.

Question 4

Relay neurons

Answer 4

These connect the sensory neuron to the Motor or other relay neurons. They have short dendrites and axons.

Question 5

Motor neurons

Answer 5

Theses connects the CNS to effectors such as muscles and glands. They have shirt dendrites and long axons.

Question 6

Cell body (soma)

Answer 6

Factory of the neuron. Contains the nucleus and produces all the necessary proteins that a neuron requires to function

Question 7

Nucleus

Answer 7

Contains genetic material within the neuron

Question 8

Dendrites

Answer 8

These Branch like features profuse from the cell body. Carry nerve impulses from neighbouring neurons towards the cell body

Question 9

Axon

Answer 9

This carries the electrical impulse from the cell body, down the length of the neuron. It is covered in myelin sheath.

Question 10

Myelin sheath

Answer 10

This a fatty layer, which surrounds and protects the axon. It helps to speed up the electrical transmission of the impulse.

Question 11

Nodes of ranvier

Answer 11

These are the gaps between the myelin sheath. Their purpose is to speed up the transmission of the impulse, by forcing it to ‘jump’ across the gaps along the axon.

Question 12

Terminal buttons

Answer 12

Located at the end of an axon. They communicate with the next neuron that is on the other side of the synaptic cleft