When a Depolarizing Graded Potential Makes the Axon Membrane Depolarize

question 34

Multiple Choice

When a depolarizing graded potential makes the axon membrane depolarize to threshold,

• A) ligand-gated Ca⁺² channels close rapidly.
• B) voltage-gated Ca⁺² channels open rapidly.
• C) ligand-gated Na⁺ channels close rapidly.
• D) voltage-gated Na⁺ channels open rapidly.
• E) none of these choices.

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Definitions:

FMVSS-121

Federal Motor Vehicle Safety Standards 121, which sets the requirements for air brake systems in heavy-duty vehicles to ensure safety through proper functionality and performance.

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The decrease in air pressure within a system, often due to leaks or inefficiencies, which can affect system performance.

Tractor-Protection Valve

A safety device in trucks that prevents air loss in the tractor if there's a leak in the trailer, ensuring the tractor's braking system remains functional.