Final answer:
The buccinator muscle at its insertion interacts with the skin, not bone, allowing for facial expressions by moving the skin when contracted. This muscle compresses the cheek, aiding in diverse functions like whistling, sucking, and chewing.
Step-by-step explanation:
At its insertion, unlike at its origin, the buccinator muscle does not move bone. Instead, the muscle fibers are interwoven with connective tissue and the dermis of the skin, allowing for the movement of the skin to create facial expressions when the muscle contracts. The buccinator is a major muscle in the face responsible for compressing the cheek, facilitating actions such as whistling, blowing, and sucking, as well as assisting with chewing. This muscle plays a critical role in the function of the oral cavity, keeping food from falling out of the mouth during chewing and playing a part in speech.