The Biceps runs down the anterior or front side of the humerus and makes up approximated 1/3 of the muscle mass of the upper arm..
The Biceps are among the most famous muscles in the body. When somebody asks you to "make a muscle", they aren't asking you to flex your hamstrings. They want to see your biceps!
he primary function of the Bicep muscle is to move the forearm towards the shoulder (elbow flexion).
The secondary function of the Bicep is supination of the forearm. This means turning the hand from a palms-down position to a palms-up position.