| A | B |
|---|
| Abduction | Moving a muscle away from the midline of the body |
| Extension/Extensor Muscle | Produces extension when it contracts |
| Myosin | The thick protein filament in the muscle fiber |
| Lactic Acid | A colorless, syrupy, organic acid formed in sour milk and produced in the muscle tissues during difficult exercise |
| Skeletal Muscle | Muscles that are connected to the skeleton to form part of the mechanical system that moves the limbs and other parts of the body; responds quickly, but tires quickly. These muscles are also striated |
| Smooth/Visceral Muscle | Involuntary controlled muscles lining blood vessels, digestive system, and uterus; responds slowly, but never tires |
| Cardiac Muscle | Found only in the heart; responds quickly and doesn’t get tired. Muscles are also striated and involuntary |
| Tendons | Cordlike, white band of non-elastic, fibrous, connective tissue that attaches a muscle to bone |
| Ligaments | Fibrous bands that hold two bone ends together in a synovial joint |
| Antagonists | Muscle that does the opposite of the agonist |
| Myofibril | Thin filament (actin) and thick filament (myosin) within the muscle fiber that give it its characteristic striated appearance |
| Sarcomeres | Portion of striated muscle that lies between the two adjacent dark lines |
