Mineral forming 90% of the cations of blood plasma is

Options

A. Mg
B. Ca
C. K
D. Na.

Answer

To determine the mineral that forms 90% of the cations in blood plasma, we will analyze each option provided: magnesium, calcium, potassium, and sodium.

### Step-by-Step Solution:

1. **Evaluate Magnesium**:
- Magnesium is an essential mineral, primarily known for being a key component of chlorophyll in plants.
- While it plays various roles in the body, it does not constitute a significant portion of the cations in blood plasma.
- **Conclusion**: Magnesium is not the correct answer.

2. **Evaluate Calcium**:
- Calcium is the most abundant mineral in the human body and is vital for various physiological functions, including bone health and muscle contraction.
- However, it is not the predominant cation in blood plasma.
- **Conclusion**: Calcium is not the correct answer.

3. **Evaluate Potassium**:
- Potassium is crucial for nerve transmission and muscle function.
- Although it is an important cation, it does not make up the majority of cations in blood plasma.
- **Conclusion**: Potassium is not the correct answer.

4. **Evaluate Sodium**:
- Sodium is recognized as the most abundant cation in blood plasma.
- It plays a critical role in maintaining fluid balance and is also involved in nerve transmission.
- Sodium constitutes approximately 90% of the cations found in blood plasma.
- **Conclusion**: Sodium is the correct answer.

### Final Answer:
The mineral forming 90% of the cations of blood plasma is **sodium**.

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