Which of These Statements Correctly Describes Contraction in Skeletal and Smooth

question 65

Multiple Choice

Which of these statements correctly describes contraction in skeletal and smooth muscle?

• A)In skeletal muscle, calcium ion mediates changes in thin filaments that lead to cross-bridge activity; in smooth muscle, calcium ion mediates changes in thick filaments that lead to cross-bridge activity.
• B)In skeletal muscle, troponin and tropomyosin are regulatory proteins; in smooth muscle, troponin is the only regulatory protein on thick filaments.
• C) In skeletal muscle, calcium ion binds to troponin; in smooth muscle, calcium ion binds to calmodulin.
• D) In skeletal muscle, calcium ion binds to calmodulin; in smooth muscle, calcium ion binds to troponin.

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Definitions:

Maintenance Stage

In behavior change models, this stage refers to the sustained effort to avoid relapse and consolidate the gains achieved during the action stage.

Relapse

A return to former unhealthy patterns.

Maintenance Stage

A phase in behavior change where individuals work to sustain new habits and prevent relapse into previous behaviors.

Exercise Program

A planned routine of physical activities designed to improve fitness or achieve specific health and fitness goals.