Why Is ATP Needed for Muscle Contraction

question 66

Multiple Choice

Why is ATP needed for muscle contraction?

• A)It causes tropomyosin to slide off the myosin binding sites of actin.
• B)It's needed for calcium release from the sarcoplasmic reticulum.
• C)It causes calcium to bind to troponin.
• D)Myosin has to physically contact the actin filament and move to pull it toward the midline of the sarcomere.

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Definitions:

Muscular Tunic

A layer commonly found in various hollow organs, like the gastrointestinal tract and bladder, composed of smooth or striated muscle that helps in movement or the maintenance of tone.

Lamina Propria

A thin layer of loose connective tissue found beneath the epithelium of many organs, providing support and nourishment.

Serosa

The outermost layer of various organs in the body, particularly in the abdominal cavity, composed of connective tissue and serving to encase and protect the organs.

Superior to Inferior

Describes a direction in anatomy going from the upper part of the body towards the lower part.