Muscle Vocabulary

3. The type of muscle responsible for automatic movements such as peristalsis. It is not under conscious control. Cells are spindle shaped with one central nucleus.
6. Specialized striated muscle that does not fatigue. It is found only in the walls of the heart and is not under conscious control (involuntary muscle) .
7. A pair of muscles whose actions oppose each other, when one contracts the other relaxes (e.g. the biceps and triceps).
13. An actin binding protein important in muscle contraction by regulating the binding of myosin.
15. Muscle cell containing a bundle of myofibrils.
16. ___________hypothesis. The theory of how thin and thick filaments slide past each other to produce muscles contraction.
17. The thin contractile protein found in muscle cells.
18. __________junction. The junction between a motor neuron and a skeletal muscle fiber. It is a specialized cholinergic synapse.
20. A complex of three proteins that bind to tropomyosin and help regulate muscle contraction by causing tropomyosin to either block or unblock the attachment of myosin to actin.
21. Muscle that is attached to bones and is responsible for the movement of bones around joints or movement of some organs, e.g. the eyes.

1. The thick myofilament protein of the sarcomere of muscle.
2. Specialized smooth ER around myofibrils in skeletal muscle fibres. It stores and releases calcium ions required for muscle contraction .
4. Make up the myofibril , can be thick (myosin) or thin (actin).
5. Is a result of anaerobic metabolism when oxygen delivery to the tissues is insufficient to support metabolic demands (e.g. periods of strenous exercise).
8. The muscle fibre that predominates during aerobic, endurance activity. They contain more mitochondria and myoglobin than the "other" type.
9. The decline in a muscle's ability to maintain force in a prolonged or repeated contraction. It is the normal result of vigorous exercise.
10. Muscle that is most responsible for a specific movement and produces most of the force required.
11. Specialized structure of muscle cells. Composed of both actin and myosin. A bundle of these make up a muscle fibre.
12. The muscle fibre that predominates during anaerobic, explosive activity. It contains less mitochondria and myoglobin than the "other" fibre types.
14. A cumulative deficit of O2 resulting from intense exercise. Low levels of O2 is made up during the recovery (rest) period.
16. The contractile element of the fiber, it is contained between two Z membranes.
19. The temporary linkage of actin and myosin filaments during muscle contraction.