In Smooth Muscle, Most of the Ca²⁺ Needed for Muscle

question 173

Multiple Choice

In smooth muscle, most of the Ca²⁺ needed for muscle contraction

• A) is in the dense bodies.
• B) enters from extracellular fluid.
• C) is attached to the intermediate filaments.
• D) must be activated by myosin kinase.
• E) is stored in the sarcoplasmic reticulum.

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Definitions:

Operating Angles

The specific angles at which certain mechanical parts, such as driveshafts, are designed to operate efficiently.

Propeller Shaft

The mechanical component used to transmit power from an engine or motor to the propeller in a boat or aircraft.

Universal Joints

Flexible joints used in drive shafts that allow for the transmission of power between shafts that are not aligned.

Driveshaft Flexibility

The ability of a driveshaft to flex or bend without breaking, to accommodate movement and alignment changes in a vehicle's drivetrain.