The electrical potential difference across the plasma memebrane at the site of depolarisation is called

Options

A. Graded potential
B. Resting potential
C. Action potential
D. None of these

Answer

To answer the question regarding the electrical potential difference across the plasma membrane at the site of depolarization, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Depolarization**:
- Depolarization refers to the process where the membrane potential becomes less negative (or more positive) than the resting potential. This typically occurs when sodium ions (Na+) flow into the neuron, causing the inside of the cell to become more positive relative to the outside.

2. **Identifying the Types of Potentials**:
- We need to evaluate the options provided:
- **Graded Potential**: This is a change in membrane potential that is proportional to the strength of the stimulus and occurs in response to external stimuli. It is not specifically associated with depolarization at a specific site.
- **Resting Potential**: This is the baseline electrical charge difference across the membrane when the neuron is not actively firing. It does not refer to depolarization.
- **Action Potential**: This is a rapid and substantial depolarization that occurs when a neuron sends an electrical signal down its axon. It is characterized by a significant change in the membrane potential at the site of depolarization.

3. **Selecting the Correct Answer**:
- Based on the definitions and characteristics of the potentials:
- The correct answer is **Action Potential** because it specifically refers to the electrical potential difference across the plasma membrane at the site of depolarization.

4. **Conclusion**:
- Therefore, the electrical potential difference across the plasma membrane at the site of depolarization is called **Action Potential**.