Action potentials occur when :

Options

A. A) a neuron receives adequate stimulation
B. B) sodium gates open in an ever accelerating way
C. C) sodium-potassium pumps kick into action
D. D) both (a) and (b)

Explanation

**Step-by-Step Solution:**

1. **Understanding Action Potentials:**
- Action potentials are rapid changes in the electrical potential across the membrane of a neuron. They are essential for the transmission of signals along the neuron.

2. **Identifying Key Events:**
- There are three main events that lead to the generation of an action potential:
- **Triggering Event:** This occurs when a neuron receives adequate stimulation, causing depolarization of the cell membrane.
- **Ion Movement:** The influx of sodium ions (Na+) into the neuron occurs, which is crucial for the depolarization phase of the action potential.
- **Repolarization:** After the peak of the action potential, potassium ions (K+) flow out of the neuron to restore the resting membrane potential.

3. **Analyzing the Options:**
- **Option A:** A neuron receives adequate stimulation. This is true as stimulation is necessary to initiate an action potential.
- **Option B:** Sodium channels open in an accelerating way. This is also true as the opening of sodium channels leads to the rapid depolarization of the neuron.
- **Option C:** Sodium-potassium pumps kick into action. This is not directly involved in the generation of the action potential but rather helps restore the resting membrane potential after the action potential has occurred.
- **Option D:** Both A and B. Since both A and B are true, this option is correct.

4. **Conclusion:**
- Based on the analysis, the correct answer is **Option D: both A and B**.

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