Question

The part of the nervous system involved in reflex action is the

• A. cerebellum
• B. spinal cord
• C. cerebrum
• D. medulla

Answer 1

The correct option is B

spinal cord

The correct answer is option B.

Explanation of correct option:

Reflex Action:

1. The spinal cord controls some actions that do not involve the brain. Its reaction is automatic and does not involve thinking about it. It is called a reflex action.
2. Thus an automatic, spontaneous and mechanical response to a stimulus controlled by the spinal cord without the involvement of the brain is called a reflex action.

Explanation of incorrect options:

Option A:

Cerebellum:

1. It is a small, egg-shaped lobe structure located at the base under the cerebrum.
2. It helps in the muscle coordination and balance of the body.

Option C:

Cerebrum:

1. It is the uppermost, largest and the most prominent part of the brain.
2. It is responsible for the sensation of pain, temperature, touch, sight, sound, taste and smell.
3. It also controls the mental activities such as memory, intelligence, thinking and reasoning.

Option D:

Medulla:

1. It is the lowermost part of the brain located at the base of the skull.
2. It controls breathing, heartbeat, coughing, sneezing and other involuntary functions.

Final answer: The part of the nervous system involved in reflex action is the spinal cord.