Reflexes

Question 1

What is a reflex?

Answer 1

• An involuntary response to a stimulus where no conscious thought is needed.
• Rapid and provides protection for survive e.g. blinking.

Question 2

What is the reflex arc and what does it consist of?

Answer 2

Reflection arc -> pathway of neurones involved in a reflex action.
Receptor -> sensory receptor -> relay neurone -> motor neurone

Question 3

What is knee jerk reflect?

Answer 3

• Helps maintain posture and balance with little conscious thought.
• Drs use reflex to check NS is working.
• Involves sensory and motor (only 1 synapse involved so very fast).

Question 4

What does Arc consist of?

Answer 4

1- stimulus (hitting quadriceps tendon causes quadriceps muscle to stretch).
2- receptor (stretch receptors)in quadriceps muscle detect change.
3- Spinal cord coordinates response.
4- The effectors (quadriceps muscle) respond by contracting, straightening the leg.

Question 5

What is an innate response?

Answer 5

Do not learn them, born with them.

Question 6

How does reflexes increase survival chance?

Answer 6

Involuntary response -> decision making areas of brain not involved -> so brain can deal with more complex responses -> stops brain from overloading.
Innate -> immediate protection
Very fast -> short, reflex arc 1/2 synapses involved.
Everyday action.