they dont u retard
The Origin
The origin of a muscle is where the muscle starts ("the starting point"). The insertion of a muscle is where the muscle ends ("the ending point"). Also, the insertion of the muscle is what moves a lot (contrary of the origin where the muscle mostly stays stationary).
origin is where the muscle is attached and is the "starting point" where the insertion is where the muscle ends "the ending point" the insertion of the muscle is what moves, while the origin in most cases stays still.
tendon
the blah .
In order to work, a skeletal muscle must have both ends connected to he skeleton. The end of a muscle that does not move is called its origin. The other end is attached to the bone it moves, and is called insertion.
Muscles are attached to bone by tendons. Bones are attached to bones by ligaments.
The bones itself do not move, but it's the muscle that moves it.
In order to work, a skeletal muscle must have both ends connected to he skeleton. The end of a muscle that does not move is called its origin. The other end is attached to the bone it moves, and is called insertion.
The muscle tissue that is attached to and moves the skeleton is called the skeletal muscle.
There are two points of attachment for a (skeletal) muscle, the origin and the insertion. The origin is the immovable (or slightly movable) part. The insertion moves towards the origin.
Essentially the second half of your question is what happens when a muscle contracts on a larger scale. On a much smaller scale, the contraction of muscle is caused by myosin proteins pulling themselves along the surface of an actin protein, which shortens the muscle. Muscles pull the bone that they are attached to at their point of insertion towards their point of origin.