Two Fundamental Concepts About the Ion Channels of a "Resting

question 34

Multiple Choice

Two fundamental concepts about the ion channels of a "resting" neuron are that the channels ________.

• A) are always open, but the concentration gradients of ions frequently change
• B) are always closed, but ions move closer to the channels during excitation
• C) are open or closed depending on their type, and are specific as to which ion can traverse them
• D) open in response to stimuli, and then close simultaneously, in unison

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Definitions:

Epithelial Surface

The layer of cells covering the surfaces of the body, including the skin, organs, and internal passageways.

Bloodstream

The flowing blood within the circulatory system of the body, transporting oxygen, nutrients, and waste products.

Collagenous Fibers

Strong, flexible fibers made of collagen that are a major component of connective tissue in the body.

Ligaments

Strong, fibrous tissues that connect bones to other bones, providing stability and support in joints.