13.8 reflexes

Question 1

What is a reflex arc

Answer 1

Pathway of nuerones involved in a reflex action

Question 2

How does neurones travel along a reflex arc

Answer 2

When receptor detects stimuli and creates an action potential in sensory neurone
The sensory neurone carries impulse to spinal cord and the relay neurone connects the sensory neurone to the motor neurone in spinal cord
Motor neurone carries impulse to effector

Question 3

What type of reflex is the knee jerk reflex

Answer 3

A spinal reflex which means it doesn’t include the brain

Question 4

What happens in a knee jerk reflex

Answer 4

Leg is tapped below the knee cap
The patella tendon stretches and stimuli initiate a reflex arc causing extensor muscles of thigh to contract as the same time the relay neurone inhibits the motor neurone of the flexor muscle

Question 5

Why is the knee jerk reflex needed

Answer 5

It is used by the body to help maintain posture and balance and allows you to maintain balanced with little thought

Question 6

What type of reflex is the blinking reflex

Answer 6

Cranial reflex - occurs in the brain not the spinal cord

Question 7

When does the blinking reflex occur

Answer 7

It occurs when the cornea is stimulated and is the involuntary blinking of the eyelids

Question 8

Why is the blinking reflex needed

Answer 8

Used to keep cornea safe from damage like foreign bodies

Question 9

When is the blinking reflex tested

Answer 9

When examining unconscious patients and if it is present it indicates the lower brain stem is functioning
Determines if patients are brain dead

Question 10

What are reflexes important for

Answer 10

Survival
They avoid the body being harmed or reduce severity of damage and
It’s involuntary response and prevents overloading of stimuli