| A | B |
| skeletal muscles | attached to bones |
| smooth muscles | involuntary muscles found in organs |
| cardiac muscles | makes up the heart |
| sphincter muscles | circular muscles that control passage of substances |
| contractibility | the ability to shorten or contract |
| excitability | ability to respond to to stimuli |
| extensibility | ability to be stretched |
| elasticity | ability to return to original length when relaxing |
| origin | attached to a fixed structure or bone; moves least during contraction |
| insertion | attached to a movable part or bone and moves most during contraction |
| belly | central body of the muscle |
| prime mover | muscles that produce movement in a single direction |
| antagonist | moves opposite of the prime mover |
| synergists | muslces that help to steady a movement or stabalize joint activity |
| all or none law | when stimulated, muscles contract all the way or not at all |
| muscle fatigue | muscle soreness caused by a build up of lactic acid in the muscles from contracting without oxygen |
| muscle tone | muscles slightly contracted and ready to pull |
| isotonic | muscle contraction producing movement |
| isometric | muscle contractions without movement |
| atrophy | muscles shrink from lack of use |
| hypertrophy | muslces become enlarged from exercise |
| strength | ability to do work |
| physiotherapy | treatment of injury or disease using light, heat/cold, massage, electricity and exercise |
| intramuscular | into the muscle |