In a nerve cell potasium concentration is

Options

A. less on outer side
B. greater on outer side
C. equal on both sides
D. none of these

Answer

To determine the potassium concentration in a nerve cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Context**:
- In a nerve cell, the concentration of potassium ions (K+) is crucial for maintaining the resting membrane potential and for the generation of action potentials.

2. **Comparing Concentrations**:
- The question asks about the potassium concentration in relation to the inside and outside of the nerve cell.

3. **Typical Potassium Concentration Values**:
- Inside the nerve cell (intracellular): Approximately 500 mM (millimolar).
- Outside the nerve cell (extracellular): Approximately 25 mM.

4. **Analyzing the Options**:
- The options given are:
a) Lesser outside
b) Greater outside
c) Equal on both sides
d) None of the above

5. **Evaluating Each Option**:
- **Option a (Lesser outside)**: This is correct because the concentration of potassium is significantly higher inside the cell compared to outside.
- **Option b (Greater outside)**: This is incorrect as the concentration is lower outside.
- **Option c (Equal on both sides)**: This is incorrect since the concentrations are not equal.
- **Option d (None of the above)**: This is also incorrect as option a is valid.

6. **Conclusion**:
- The correct answer is that the potassium concentration is greater inside the cell and lesser outside. Therefore, the answer is **Option a: Lesser outside**.