During Which Phase of an Excitation-Contraction Cycle Does Depolarization Occur

question 19

Multiple Choice

During which phase of an excitation-contraction cycle does depolarization occur?

• A)excitation
• B)inhibition
• C)contraction
• D)relaxation

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Definitions:

Stroma

The supportive tissue of an epithelial organ, tumor, gonad, etc., consisting of connective tissues and blood vessels.

ATP Synthase

Complex of proteins in the cristae of mitochondria and thylakoid membrane of chloroplasts that produces ATP from the diffusion of hydrogen ions across a membrane.

Coenzyme

Nonprotein organic molecule that aids the action of the enzyme to which it is loosely bound.

Light Reactions

The initial phase of photosynthesis where solar energy is converted into chemical energy in the form of NADPH and ATP.