THE STRUCTURE AND FUNCTIONS OF NEURONS

Question 1

Neuron

Answer 1

• The basic building blocks of the nervous system; nerve cells that process and transmit messages through electrical and chemical signals
• 100 billion in the human nervous system, 80% located in the brain

Question 2

Types of neuron

Answer 2

• Sensory
• Relay
• Motor

Question 3

Sensory neuron

Answer 3

• Carry nerve impulses from the peripheral nervous system to the CNS
• Found in receptors such as the eyes, ears, tongue and skin.
• Long dendrites and short axons

Question 4

Relay neurons

Answer 4

• Connect the sensory neurons to the motor or other relay neurons
• Short dendrites and short axons

Question 5

Motor neurons

Answer 5

• Connect the CNS to effectors such as muscles and glands; release neurotransmitters which bind to receptors
• Short dendrites and long axons

Question 6

The cell body (soma)

Answer 6

• includes a nucleus, which contains the genetic material of the cell

Question 7

Dendrites

Answer 7

• Carry electrical impulses towards the cell body

Question 8

Axon

Answer 8

• Carries electrical impulses away from the cell body

Question 9

Myelin sheath

Answer 9

• Insulates the axon and improves electrical transmission

Question 10

terminal buttons

Answer 10

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

Question 11

Specialist functions of neurotransmitter example

Answer 11

ACh is found at each point where a motor neuron meets a muscle, and upon its release it will cause muscles to contract