Relflex Arc

Question 1

Part 1

Answer 1

When a stimulus is detected by receptors , impulses are sent along a sensory neurone to a relay neurone in the CNS

Question 2

Part 2

Answer 2

When the impulses reach a synapse between the sensory neurone and the relay neurone , they trigger chemicals to be released. These chemicals cause impulses to be sent along the relay neurone.

Question 3

Part 3

Answer 3

When the impulses reach a synapse between the relay neurone and a motor neurone, the same thing happens. Chemicals are released and cause impulses to be sent along the motor neurone .

Question 4

Part 4

Answer 4

The impulses then travel along the motor neurone to the effector

Question 5

Part 5

Answer 5

The muscle then contracts and moves your hand away from the stimulus