Structure And Function Of the Living Organisms: How Impulse Travels in Reflex Movement

Reflex movements occur without conscious awareness and are faster than voluntary actions. An example is the quick withdrawal of a hand from a hot object to prevent injury. Reflex actions are processed in the spinal cord and brainstem, bypassing the brain for faster response. The reflex arc involves a stimulus being detected by receptors, sending an impulse through sensory nerves to the spinal cord, and then through motor nerves to muscles, resulting in a quick reaction.

What distinguishes reflex movements from conscious movements?

• They are voluntary and deliberate.

• They are slower and require brain processing.

• They occur without awareness and are faster.

• They involve complex decision-making.

Where are reflex movements primarily processed?

• In the brain only.

• In the spinal cord and medulla.

• In the heart.

• In the lungs.

Which part of the body first receives the heat stimulus in a reflex action?

• The brain.

• The spinal cord.

• The motor nerve.

• The skin receptor.

What role does the motor nerve play in reflex actions?

• It receives the initial stimulus.

• It processes the stimulus in the brain.

• It sends the impulse back to the skin.

• It carries the impulse to the muscles.

How does the arm respond to a heat stimulus in a reflex action?

• It moves towards the heat.

• It waits for a conscious decision.

• It remains still.

• It moves away quickly to avoid harm.