Neurons

Question 1

What is a neuron?

Answer 1

Nerve cells that process and transmit messages through electrical and chemical signals

Question 2

What is a sensory neuron?

Answer 2

• Carry messages from the PNS to the CNS
• Have long dendrites and short axons

Question 3

What is a relay neuron?

Answer 3

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

Question 4

What is a motor neuron?

Answer 4

• Connect the CNS to effectors such as muscles and glands
• Have short dendrites and long axons

Question 5

What is the structure of a neuron?

Answer 5

• Nucleus
• Dendrites
• Cell body
• Axon
• Myelin sheath
• Nodes of Ranvier
• Terminal buttons

Question 6

What is the cell body?

Answer 6

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

Question 7

What is the nucleus?

Answer 7

Contains the genetic material within the neuron

Question 8

What are dendrites?

Answer 8

• Branch-like features that protrude from the cell body
• Carry nerve impulses from neighbouring neurons towards the cell body

Question 9

What is the axon?

Answer 9

Carries the electrical impulse from the cell body, down the length of the neuron

Question 10

What is the myelin sheath?

Answer 10

• Fatty layer, which surrounds and protects the axon
• Helps to speed up the electrical transmission of the impulse

Question 11

What are the nodes of Ranvier?

Answer 11

• Gaps between the myelin sheath
• Speed up the transmission of the impulse, by forcing it to ‘jump’ across the gaps along the axon

Question 12

What are the terminal buttons?

Answer 12

• Located at the end of the axon
• Communicate with the next neuron that is on the other side of the synaptic cleft