Which Membrane Protein Transport Process Plays an Important Role in Terminating

question 49

Multiple Choice

Which membrane protein transport process plays an important role in terminating the contraction of cardiac muscle?

• A) Ca ²⁺-ATPase pumps move Ca²⁺ from the T-tubule back into the sarcoplasmic reticulum.
• B) Na⁺/K⁺-ATPase pumps move Na⁺ back into the cytosol and K⁺ back into the T-tubule lumen.
• C) Ca²⁺-ATPase pumps move Ca²⁺ from the cytosol back into the sarcoplasmic reticulum.
• D) Na⁺/Ca²⁺-exchangers move Na⁺ out of the cytosol in exchange for Ca²⁺ movement into the sarcoplasmic reticulum.
• E) Na⁺/K⁺-ATPase pumps move Na⁺ and K⁺ back out of the cell.

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Definitions:

Carbon-Carbon Double Bond

A chemical bond between two carbon atoms involving four bonding electrons instead of the usual two, creating a region of high electron density.

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The branch of mathematics concerned with the properties, measurement, and relationships of points, lines, angles, surfaces, and solids.

Alkene

Hydrocarbons that are unsaturated and possess a minimum of one double bond between carbon atoms, identified by the formula CnH2n.

3-Methylpent-2-Ene

An unsaturated hydrocarbon with the formula C6H12, highlighting a branch and a double bond in its structure.