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:

Intersex

A term that refers to individuals who are born with genitalia, chromosomes, and/or reproductive organs that do not fit typical binary notions of male or female bodies.

Ambiguous Genitalia

A condition where a newborn's external genitals do not appear clearly male or female.

Sex

Your sex depends on your genetic makeup—specifically, whether your sex chromosome is XX (female), XY (male) or X, XXY, XXYY, and so on. The latter sex chromosomes often result in a person who does not fit conventional male or female sex categories.

Chromosomes

Structures within cells that contain DNA and genetic information, playing a key role in determining the characteristics of living organisms.