Which Statement About Ion Movements and Ventricular Muscle Cells Is

question 90

Multiple Choice

Which statement about ion movements and ventricular muscle cells is false?

• A) Sustained opening of Ca²⁺ channels is responsible for the extended plateau phase of the action potential.
• B) Cardiac muscle is stimulated to contract when Ca²⁺ is available to bind with troponin.
• C) For ventricles to fill again, Na⁺ must be removed from the sarcoplasm.
• D) Ca²⁺ ions are actively transported out of the sarcoplasm and into the sarcoplasmic reticulum.
• E) When Ca²⁺ remains in the sarcoplasm, ventricular muscle cells continue to contract.

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Definitions:

Monopolistically Competitive Industry

A market structure characterized by many producers selling differentiated products, leading to competition based on product features as well as price.

ATC

The total cost per unit of output, calculated by dividing the total cost by the amount of output produced.

Long-Run Equilibrium

A state in which all factors of production are fully adjusted to the economic conditions, leading to a situation where there is no tendency for change.