Depolarisation is the

Options

A. Active process
B. Passive process
C. Both active and passive process
D. First it is passive and than it becomes a

Answer

To answer the question "Depolarisation is the...", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Depolarization**:
- Depolarization refers to a change in the membrane potential of a neuron. It occurs when the inside of the neuron becomes less negative (or more positive) compared to the outside.

2. **Role in Nerve Impulses**:
- Depolarization is crucial for the initiation of nerve impulses. When a neuron is stimulated, sodium channels open, allowing Na+ ions to flow into the cell, leading to depolarization.

3. **Voltage Dependency**:
- The process of depolarization is voltage-dependent. This means that it occurs when the membrane potential reaches a certain threshold, which triggers the opening of additional ion channels.

4. **Classification of the Process**:
- Since depolarization involves the movement of ions across the membrane and does not require energy (ATP), it is classified as a passive process. This is because it relies on the natural movement of ions down their concentration gradient.

5. **Conclusion**:
- Therefore, we can conclude that depolarization is a passive process.

### Final Answer:
Depolarization is a passive process.

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