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:

Pinion

A small gear that engages with a larger gear or rack, often used to convert rotational motion to linear motion or vice versa.

Mechanical Advantage

The factor by which a mechanism multiplies the force put into it, enabling the lifting or moving of heavier loads with less effort.

Pitch Diameters

The effective diameter of a screw thread, halfway between the crests and roots, used in measuring and specifying thread sizes.

Diametral Pitches

Diametral pitches refer to the number of teeth per inch of the diameter of a gear, which determines the size of the teeth and the pitch of the gear.