Progression Through the Phases of the Cell Cycle Is Regulated

question 71

Multiple Choice

Progression through the phases of the cell cycle is regulated by fluctuating concentrations of ____.

• A) microtubules
• B) actin
• C) cyclins
• D) cyclin-dependent kinases
• E) histones

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Definitions:

Synaptic Vesicles

Small sacs within presynaptic nerve terminals that contain neurotransmitters, critical for transmission of nerve impulses.

Exocytosis

The process by which a cell transports secretory products through the cytoplasm to the plasma membrane and then into the extracellular environment.

Action Potential

A rapid change in electrical potential across the membrane of a nerve or muscle cell when it is stimulated, leading to transmission of an electrical impulse.

Gap Junctions

Specialized intercellular connections that allow for the direct transfer of ions and molecules between neighboring cells, facilitating communication and coordination of activity.