Short Quiz On Muscles

The insertion of the extensor digitorum longus is not the tibial tuberosity. The extensor digitorum longus inserts on the middle and distal phalanges of the toes, not on the tibial tuberosity.

The rectus abdominis is a paired muscle located in the abdomen, commonly known as the "six-pack" muscle. Its primary action is to flex the vertebral column, which means it helps to bend the spine forward. This muscle is responsible for movements like crunches or sit-ups, where the upper body is brought closer to the legs by flexing the spine. Elbow flexion, hip extension, and dorsiflexion are actions performed by other muscle groups and not the rectus abdominis.

The supraspinatus muscle originates from the supraspinous fossa. The supraspinous fossa is a depression on the scapula bone located above the spine. This is where the muscle begins its attachment before it extends and inserts into the greater tubercle of the humerus. The supraspinatus muscle plays a crucial role in shoulder movement and stability, particularly in initiating abduction of the arm.

The insertion of the pectoralis minor muscle is the coracoid process of the scapula. The pectoralis minor originates from the third, fourth, and fifth ribs, and it inserts onto the coracoid process. This muscle is responsible for stabilizing and depressing the scapula, as well as assisting in the movement of the shoulder joint.