THE STRUCTURE AND FUNCTION OF NEURONS

Question 1

What is a neuron?

Answer 1

the basic building blocks of the nervous system, neurons are nerve cells that process and transmit messages through electrical and chemical signals

Question 2

What is a sensory neuron?

Answer 2

These carry messages from the PNS (peripheral nervous system) to the CNS. They have long dendrites and short axons

Question 3

what is a relay neuron?

Answer 3

These connect the sensory neurons to the motor or other neurons. They have short dendrites and short axons

Question 4

Describe the cell body

Answer 4

The cell body includes a nucleus, which contains the genetic material of the cell.

Question 5

What are dendrites?

Answer 5

Branch-like structures called dendrites carry nerve impulse from neighboring neurons towards the cell body.

Question 6

What is an axon?

Answer 6

The axon carries impulses away from the cell body down the length of the neuron.

Question 7

Describe the myelin sheath

Answer 7

The axon is covered in a fatty layer of myelin sheath that protects the axon and speeds up electrical transmission of the impulses

Question 8

Describe the nodes of Ranvier

Answer 8

Nodes of Ranvier speeds up the transmission of the impulse by forcing it to jump across the gaps along the axon

Question 9

Describe the terminal buttons

Answer 9

At the end of the neuron and are responsible for sending the signal on to other neurons

Question 10

What is electric transmission?

Answer 10

• The firing of a neuron
• Neurons in a resting state inside the cell are negatively charged compared to the outside.
• When activated by stimuli, the inside of the cell becomes positively charged for a split second causing an action potential to occur.
• This creates an electrical impulse that travels down the axon towards the end of the neuron.

Question 11

What is a motor neuron?

Answer 11

these connect the CNS to effectors such as muscles and glands. They have short dendrites and long axons