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Explanation:
While the biceps crosses both the shoulder and elbow joints, its main function is at the elbow where it flexes the forearm and supinates the forearm. Both these movements are used when opening a bottle with a corkscrew: first biceps unscrews the cork (supination), then it pulls the cork out (flexion).
Answer:
The tendon of this muscle is attached to the inner protrusion near the head of the radius, a bone of the forearm. The biceps brachii bends the forearm toward the upper arm and is thus used in lifting and pulling movements. It also supinates the forearm (turns the palm forward or upward).
The biceps brachii is a prominent muscle on the front side of the upper arm. It originates in two places: the coracoid process, a protrusion of the scapula (shoulder blade); and the upper glenoid cavity, the hollow for the shoulder joint. The tendon of this muscle is attached to the inner protrusion near the head of the radius, a bone of the forearm. The biceps brachii bends the forearm toward the upper arm and is thus used in lifting and pulling movements. It also supinates the forearm (turns the palm forward or upward). The size of the biceps brachii is a conventional symbol of bodily strength.
The biceps femoris is one of the hamstring muscles at the back of the thigh. It originates in two places: the ischium (lower, rear portion of the pelvis, or hipbone) and the back of the femur (thighbone). The fibres of these two origins join and are attached at the head of the fibula and tibia, the bones of the lower leg. This muscle extends the thigh, rotates it outward, and flexes the leg at the knee.
This article was most recently revised and updated by Chelsey Parrott-Sheffer, Research Editor.
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The structure of striated muscleStriated muscle tissue, such as the tissue of the human biceps muscle, consists of long, fine fibres, each of which is in effect a bundle of finer myofibrils. Within each myofibril are filaments of the proteins myosin and actin; these filaments slide past one another as the muscle contracts and expands. On each myofibril, regularly occurring dark bands, called Z lines, can be seen where actin and myosin filaments overlap. The region between two Z lines is called a sarcomere; sarcomeres can be considered the primary structural and functional unit of muscle tissue.
muscle: Muscles that work skeletons
…many muscles, such as the biceps in the human arm, are composed of relatively long fibres lying nearly parallel to each other. These parallel muscles are attached to tendons or apodemes (in arthropods, chitinous rods that serve as sites for muscle attachment) only at their extreme ends. Since muscle fibres…
Muscles of the upper arm.
arm
…the elbow; the brachialis and biceps muscles act to bend the arm at the elbow. A number of smaller muscles cover the radius and ulna and act to move the hand and fingers in various ways. The pectoralis muscle, anchored in the chest, is important in the downward motion of…
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