Which muscle fiber arrangement is characteristic of the pectoralis major muscle?

• A. Parallel
• B. Pennate
• C. Circular
• D. Convergent

Answer: (D)

Verified step by step guidance

1. Understand the concept of muscle fiber arrangements: Muscle fibers can be arranged in different patterns, including parallel, pennate, circular, and convergent. Each arrangement has unique structural and functional characteristics.
2. Define the convergent muscle fiber arrangement: In a convergent arrangement, muscle fibers spread out from a broad origin and converge to a single, narrow insertion point. This allows for versatile movement and force generation.
3. Identify the anatomy of the pectoralis major: The pectoralis major is a large, fan-shaped muscle located in the chest. It has a broad origin from the clavicle, sternum, and ribs, and its fibers converge to insert on the humerus.
4. Compare the pectoralis major's structure to the convergent arrangement: The broad origin and narrow insertion of the pectoralis major match the characteristics of a convergent muscle fiber arrangement.
5. Conclude that the pectoralis major muscle exhibits a convergent fiber arrangement based on its anatomical structure and functional design.