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The muscular system is a common subject of study in biology, especially at the collegiate level. The general function of a muscle is to contract, which brings the ends together. This frequently serves to bring one bone toward another, although some muscles such as sphincters may not be attached to any bones at all. A study of a particular muscle should include learning its name, action, insertion, origin, nerve supply and blood supply.

Difficulty:

Moderately Challenging

Instructions

Things You'll Need

• Muscle chart

1. • 1

     Provide the name of the muscle and its meaning. Muscles typically have a Latin name or Greek name which describes its shape or function. For example, the term biceps brachii means "two heads of the arm" in Latin. This is the largest muscle in the arm and it has two distinct heads.

   • 2

     Describe the action of the muscle. Some muscles perform a single, specific action while others make multiple movements. For example, the biceps brachii supinates the forearm and stabilizes the anterior part of the shoulder. It also flexes the forearm at the elbow when the forearm is supinated.

   • 3

     Identify the origins of the muscle. These are the structures where the muscle is attached that don't move when the muscle contracts. For example, the long head of the biceps brachii originates on the cartilaginous rim around the socket of the shoulder joint known as the glenohumeral labrum. The long head of the biceps also originates from the scapula just above the shoulder socket at a point known as the supraglenoid tubercle. The short head of the biceps originates from a small hook-like structure on the lateral edge of the scapula known as the coracoid process.

   • 4

     Examine the insertion points of the muscle. These are the structures where the muscle is attached that do move when the muscle contracts. The biceps brachii inserts into a bulge on the medial side of the radius called the bicipital tuberosity. It also inserts into the fascia of a broad, flat layer of tendons at the elbow known as the bicipital aponeurosis.

   • 5

     Explain the blood supply and nerves of the muscle. The blood supply for the biceps brachii is the brachial artery. Its nerves come from the lateral cord of the fifth and sixth cervical nerves.