Which element accounts for 93% of total cations in blood or which is the principal cation in the plasma of blood?

Options

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

Answer

To answer the question regarding which element accounts for 93% of total cations in blood or which is the principal cation in the plasma of blood, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Cations**:
- Cations are positively charged ions. In the context of blood plasma, we are interested in identifying the principal cation.

2. **Identifying Options**:
- We have four options to consider:
- Option 1: Sodium (Na)
- Option 2: Potassium (K)
- Option 3: Calcium (Ca)
- Option 4: Sugar (not a cation)

3. **Researching Blood Electrolytes**:
- The most abundant electrolyte in blood plasma is Sodium. It plays a crucial role in maintaining osmotic pressure and is vital for nerve and muscle function.

4. **Evaluating Sodium's Presence**:
- Sodium accounts for approximately 93% of the total cations present in blood plasma. This makes it the principal cation in this fluid.

5. **Conclusion**:
- Based on the information gathered, the correct answer to the question is Option 1: Sodium (Na).

### Final Answer:
The element that accounts for 93% of total cations in blood, or the principal cation in the plasma of blood, is Sodium (Na).

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