Practice Questions

Correct: Cardiac muscle possesses intrinsic rhythmicity and resists fatigue, allowing continuous contraction. A: Skeletal muscle fatigues comparatively quickly. B: Smooth muscle contracts slowly and is not intrinsically rhythmic in the same manner. D: Tendons do not contract. Concept: Functional adaptation of cardiac muscle.

Correct: Skeletal muscles attach to bones and allow voluntary movement. A: Cardiac muscle functions only in the heart. B & D: Smooth (visceral) muscles control internal organs. Concept: Functional classification of muscles.

Correct: Cardiac muscle fibers branch and connect through intercalated discs. A & D: Describe skeletal muscle. C: Describes smooth muscle. Concept: Structural comparison of muscle tissues.

Correct: Smooth muscle contracts slowly and involuntarily in the walls of internal organs. A & D: Skeletal muscle is voluntary. B: Cardiac muscle is limited to the heart. Concept: Physiological role of smooth muscle.

Correct: Cardiac muscle is striated and usually has one centrally placed nucleus. A: Smooth muscle lacks striations. B: Skeletal muscle has multiple peripheral nuclei. D: Ligaments are connective tissues. Concept: Microscopic comparison of muscles.

Correct: Cardiac muscle contracts involuntarily under the control of the autonomic nervous system and pacemaker cells. A: It is living tissue. C: It contracts continuously. D: It is confined to the heart. Concept: Control of muscle contraction.

Correct: Smooth muscle in blood vessel walls controls vasoconstriction and vasodilation. A: Skeletal muscle moves bones. C: Cardiac muscle forms the heart. D: Tendons connect muscles to bones. Concept: Function of smooth muscle.

Correct: Branched fibers connected by intercalated discs are unique to cardiac muscle. A: Skeletal fibers are long and unbranched. B: Smooth muscle is spindle-shaped. D: Not muscle tissue. Concept: Histology of cardiac muscle.

Correct: Skeletal muscles are attached to bones and produce voluntary body movements. A: Cardiac muscle pumps blood. B & D: Smooth (visceral) muscles control internal organs. Concept: Voluntary muscle action.

Correct: Smooth muscle consists of spindle-shaped, non-striated, uninucleate cells found in hollow organs. A: Skeletal muscle is striated and multinucleated. B: Cardiac muscle is branched and found only in the heart. D: Tendons are connective tissue. Concept: Identification of smooth muscle.