When an Action Potential from a Motor Neuron Arrives at the Neuromuscular

question 64

Multiple Choice

When an action potential from a motor neuron arrives at the neuromuscular junction (NMJ) , a series of events occurs that leads to muscle contraction. Which of the following events will occur last (that is, after all of the others listed below) ?

• A) acetylcholine (ACh) release
• B) conformational change in troponin
• C) depolarization of the muscle cell
• D) release of Ca²⁺ from the sarcoplasmic reticulum

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Definitions:

Grabbing Brakes

A condition where the brakes engage suddenly and forcefully at the slightest touch, often due to uneven brake pad wear or contamination.

Pedal Pulsation

A vibration or pulsing sensation felt in the brake pedal, often indicative of warped brake rotors.

Brake Fluid Contamination

The process by which foreign substances enter the brake fluid, potentially causing failure of the braking system by reducing its performance.

Rotor Thickness

The measurement of a brake rotor's width, critical for maintaining effective braking performance and safety.