Question

The transmembrane potential at which an action potential begins is known as :

• A. Nerve impulse
• B. Reflective impulse
• C. Threshold
• D. Stimulation

Hint:

Threshold potential is the minimum membrane potential required to trigger an action potential in a neuron.

Answer 1

The Correct Option is C

Concept: An action potential is an electrical signal generated in a neuron when the membrane potential reaches a critical level. This critical transmembrane potential is called the threshold potential. Once the threshold is reached, rapid depolarization occurs and a nerve impulse is generated.

Step 1: Understand action potential generation.
A neuron remains at resting potential until sufficient stimulation causes the membrane potential to reach a critical value.

Step 2: Identify the term for this critical potential.
The transmembrane potential at which an action potential begins is called: \[ \text{Threshold} \] Hence, the correct answer is: \[ \boxed{(C)\ \text{Threshold}} \]