Question

An example of autonomous nervous system is

• A. swallowing of food
• B. pupillary reflex
• C. peristalsis of intestine
• D. knee-jerk response

Answer 1

The correct option is C

peristalsis of intestine

The correct option is C.

Explanation of the correct option:

1. The organs of our body (viscera), the heart, intestines, and stomach, are regulated by a branch of the nervous system known as the autonomic nervous system. It consists of autonomic neurons that conduct impulses from the central nervous system (brain and/or spinal cord) to glands, smooth muscle, and cardiac muscle.
2. Autonomic nervous system neurons are responsible for regulating the secretions of certain glands (i.e., salivary glands) and the regulation of heart rate and peristalsis (contraction of smooth muscle in the digestive tract), among other functions.
3. Thus, peristalsis of the intestines is an example of the action of the autonomous nervous system.

Explanation of the incorrect option:

Option A:

Swallowing of food initially is an example of the somatic nervous system.

Option B:

The pupillary reflex is an unconditioned reflex.

Option C:

The knee-jerk response is a reflex action referring to the monosynaptic reflex action.

Final answer: An example of an autonomous nervous system is the peristalsis of the intestine.