Which muscle covers the entire back of the upper arm and extends the forearm?

The muscle that covers the entire back of the upper arm and extends the forearm is the tricep. This muscle is primarily responsible for the extension of the elbow joint, playing a crucial role in straightening the arm. The tricep consists of three heads—long, lateral, and medial—which contribute to its overall function and shape, making it a prominent muscle on the back of the upper arm.

Understanding the anatomy and function of muscles is key in fields like nail technology, as it helps in procedures that involve the hands and arms. In contrast, the bicep is located at the front of the upper arm and is responsible for flexing the elbow, while the deltoid covers the shoulder and is mainly involved in shoulder movements. The pectoralis major is a chest muscle that plays no direct role in extending the forearm, focusing instead on movements of the upper arm and shoulder. Thus, recognizing the specific functions of these muscles is essential for a comprehensive grasp of human anatomy related to your field.