Question

The accessory nerve carries impulses to the sternocleidomastoid muscle. Which would be true for the accessory nerve?

autonomic


sensory


afferent


somatic

Answer 1

The accessory nerve is classified as a somatic motor nerve, being responsible for sending efferent (motor) impulses to muscles that control the head and neck movements such as in the sternocleidomastoid and trapezius muscles. It does not handle sensory or autonomic functions.

Step-by-step explanation:

The accessory nerve is primarily a somatic motor nerve that is responsible for sending impulses leading to the movement of the sternocleidomastoid and trapezius muscles, which play a vital role in the movement of the head and neck. Being a motor nerve, it carries efferent signals from the central nervous system to muscles, therefore, the correct option for the accessory nerve is 'somatic'. The accessory nerve does not carry sensory impulses (which would be afferent signals) nor is it involved with the autonomic nervous system, which handles involuntary bodily functions. The accessory nerve facilitates important functions such as turning the head, flexion of the neck, and elevating the shoulders, which is apparent during actions such as shrugging.

Answer 2

The correct answer is somatic.

The accessory nerve (cranial nerve XI) is a somatic nerve that primarily supplies the sternocleidomastoid and trapezius muscles. It is responsible for controlling the movements of the head and shoulders, such as rotating the head or shrugging the shoulders.

Autonomic nerves control involuntary functions such as heart rate, digestion, and breathing. Sensory nerves transmit information from sensory organs such as the eyes, ears, and skin to the brain. Afferent nerves refer to nerves that transmit information from the periphery to the central nervous system, while efferent nerves transmit information from the central nervous system to the periphery.