Structure And Function Of Neurones

Question 1

What are neurones

Answer 1

• neurones are the basic building blocks of the nervous system they are nerve cells which process and transmit messages through electrical and chemical signals
• most neurones are located in the brain

Question 2

Structure of neurones

Answer 2

The structure of all cells is the same but they vary in size. The structure of beige ones include:a cell body, dendrites and an axon

Question 3

What are dendrites

Answer 3

Dendrites are at one end of the neurone abs receive signals from other neurones or sensory receptors

• dendrites are connected to the cell body which includes the nucleus

Question 4

How is the impulse carried

Answer 4

The impulse is carried from the cell body along the axon
The axon is covered in a fatty layer ( the myelin sheath) which protects the axon and speeds up the electrical impulse

• at the end of the axon are terminal buttons which communicate with the next neurone in the chain across the synapse (gap)

Question 5

Sensory neurones - long dendrites short axons

Answer 5

• carry messages from sensory receptors to the CNS
• sensory receptors can be found in the eyes,ears, tongue and skin
• sensory neurons convert information from sensory reception into neural impulses
• neural impulses are passed on to the brain or spinal cord for reflex actions

Question 6

Relay (inter) neurones - short dendrites and axons

Answer 6

• connect the sensory neurone to motor or other relay neurones
• allow sensory and motor neurones to communicate with each other and are found in the CNS

Question 7

Motor neurones - short dendrites and long axons

Answer 7

• connect CNS to muscles and glands
• located in the CNS and project their axons outside the CNS
• directly or indirectly control muscles
• when stimulated the motor neurone releases neurotransmitters that bind to the receptors in the muscle and trigger a response
• leads to muscle movement