neurons

Question 1

What do neurons do?

Answer 1

Transmit electrical and chemical signals

Communication

Question 2

What are the types of neuron?

Answer 2

Sensory
Relay
Motor

Question 3

What are sensory neurons?

Answer 3

Carry messages from PNS to CNS
Long dendrites
Short axons

Question 4

What are relay neurons?

Answer 4

Connect sensory to motor or other relay
Short dendrites
Short axons

Question 5

What are motor neurons?

Answer 5

Connect CNS to effectors
Short dendrites
Long axons

Question 6

Describe the body of a neuron

Answer 6

CELL BODY includes a NUCLEUS
NUCLEUS contains genetic material of cell
DENDRITES protrude from body, carry nerve impulses towards body

Question 7

Describe the axon

Answer 7

AXON carries impulses away from cell body
Covered in MYELIN SHEATH - protects axon and speeds up transmission
Segmented by NODES OF RANVIER - speed up transmission forcing it to jump across gaps
TERMINAL BUTTONS at end of axon that communicate with next neuron

Question 8

How does a neuron fire?

Answer 8

Neuron in resting state - inside of cell is negatively charged compared to outside
Activated neuron - inside is positively charged for a second causing action potential to occur
Creates electrical impulse that travels down axon