Structure and function of neurons

Question 1

What is the function of a neuron?

Answer 1

Building blocks of the nervous system.

Neurons are nerve cells that process and transmit messages through electrical and chemical signals.

Question 2

What are the three types of neuron?

Answer 2

Sensory, relay and motor neurons.

Question 3

What is the function of a sensory neuron?

Answer 3

Carry messages from PNS to the CNS.

They have long dendrites and small axons.

Question 4

What is the function of a relay neuron?

Answer 4

Connect sensory neurons to the motor or other relay neurons.

They have short dendrites and short axons.

Question 5

What is the function of a motor neuron?

Answer 5

These connect the CNS to effectors such as muscles and glands.

They have short dendrites and long axons.

Question 6

What’s the role of the nucleus in the structure of a neuron?

Answer 6

Cell body (soma) includes a nucleus which contains the genetic material of the cell.

Question 7

What are the role of dendrites in the structure of a neuron?

Answer 7

Branch-like structures called dendrites protrude from cell body. They carry nerve impulses from neighbouring neurons towards the cell body.

Question 8

What are the role of axons in the structure of a neuron?

Answer 8

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

Covered in fatty layer called myelin sheath that protects the axon and speeds up electrical transmissions of the impulse.

At the end of axon are terminal buttons that communicate with the next neuron in the chain across a gap known as the synapse.

Question 9

What happens during the firing of neurons?

Answer 9

When neuron is in resting state, inside of cell is negatively charged.

When activated by stimulus, inside becomes positively charged for split second causing and action potential to occur.

This creates electrical impulse that travels down the axon towards the end of a neuron.