Origin vs Insertion
A muscular tissue of human mainly refers to all the contractile tissues of the body including skeletal, cardiac, and smooth muscles. Muscles are a type of connective tissue important to possess motions in organisms. The muscle shape may change as it moves, but both origin and insertion are special regions in a muscle that do not change their shape when the muscle moves. They are attachment sites of the muscle to a particular bone and are helpful to determine the location and the action of a particular muscle. Not only attachment sites but also the size, direction, and shape of the muscle also determine its action and the range of motion. One muscle may have more than one origin or insertion. The portion of a muscle that is between origin and insertion is called the belly or gaster of the muscle, which is mainly composed of muscle fibers.
Origin is the attachment site of the muscle’s tendon to a more stationary bone. It has very less movement and normally a muscle contracts towards it. Some muscles have more than one origin, for example, biceps brachii.
The attachment site of the muscle’s tendon to a more movable bone is known as the muscle’s insertion. It has the greatest motion when the muscle contracts and it tends to be more distal.
What is the difference between Origin and Insertion?
• Origin is the end that does not move when the muscle moves while insertion is the end that does move when the muscle moves.
• Origin tends to be more proximal while insertion tends to be more origin.
• Origin of a muscle attaches to a less movable bone whereas insertion of a muscle attaches to a more moveable bone.
• Insertion has less mass than the site of origin.
• When a muscle contracts, it pulls insertion towards origin.