Nervous System & Synapses and Reflexes

Question 1

Sensory receptors

Answer 1

A group of cells that can detect stimuli

Question 2

Stimulus

Answer 2

A change in the environment

Question 3

What happens after the stimulus is detected by the receptors (step-by-step)

Answer 3

• That information is converted into nervous impulses and sent along sensory neurons to the CNS
• Impulses then travel through the CNS along the relay neurones
• CNS sends information to an effector (muscle or gland) along a motor neurone
• The effector(s) accordingly respond

Question 4

Where do dendrites and dendrons carry nerve impulses?

Answer 4

Towards the cell

Question 5

Where do axons carry nerve impulses?

Answer 5

Away from the cell

Question 6

Myelin sheath

Answer 6

Surrounds the axon and acts as an electrical insulator

Question 7

Characteristics of a sensory neurone

Answer 7

• One long dendron carries nerve impulses from receptor cells to the cell body
• One long axon carries nerve impulses from the cell body to the CNS

Question 8

Characteristics of a motor neurone

Answer 8

• Many short dendrites carry nerve impulses from the CNS to the cell body
• One long axon carries nerve impulses from the cell bod to the effector cells

Question 9

Characteristics of a relay neurone

Answer 9

• Many short dendrites carry nerve impulses from sensory neurones to the cell body
• An axon carries nerve impulses from the cell body to motor neurones

Question 10

Synapse

Answer 10

The connection between two neurones

Question 11

Neurotransmitters

Answer 11

Chemicals which transfer nerve signals

Question 12

Reflexes

Answer 12

Automatic and rapid responses to the stimuli

Question 13

Reflex arc

Answer 13

The passage of information in a reflex