the muscles and the bone work together and attached
It contracts to move bones together.
Origin
muscle cells...
Diaphragm
muscle cells...
According to Anthony's Textbook of Anatomy and Physiology the origin is that point of attachment that does not move when the muscle contracts, and the point of attachment that does move when the muscle contracts is the insertion. Muscles and muscle groups that that directly perform specific movements are prime movers or agonists.
It is both. I involuntarily contracts to stabilize the spine just before you move to do something. Also, you are able to move it on your own.
A muscle becomes shorter when it contracts.
The muscle tissue's main function is to contract.
Agonist & AntagonistsAgonist is the muscle responsible for the primary movement ( muscle that contracts)Antagonist is the opposite muscle that must relax to allow the agonist to move a joint.
When a muscle contracts, it shortens in length.
A muscle that contracts shortens whereas a muscle that relaxes lengthens.