Which of the following is true for blood ?

Options

A. It is opaque and highly alkaline fluid
B. It is highly acidic fluid
C. It is slightly alkaline fluid
D. It is red coloured, opaque and slightly acidic fluid

Answer

To determine which statement is true for blood, we can analyze the characteristics of human blood based on the information provided.

### Step-by-Step Solution:

1. **Understanding the Characteristics of Blood**:
- Blood is a fluid that circulates in the body, and it has specific physical and chemical properties.

2. **Color of Blood**:
- Blood is known to be red in color due to the presence of hemoglobin, which binds to oxygen.

3. **Opacity of Blood**:
- Blood is opaque, meaning it does not allow light to pass through easily.

4. **pH Level of Blood**:
- The pH of human blood typically ranges from 7.35 to 7.45. This indicates that blood is slightly alkaline (basic) rather than acidic.

5. **Viscosity and Density**:
- Blood is denser and more viscous than water, which means it has a thicker consistency and does not flow as easily as water.

6. **Evaluating the Options**:
- Based on the characteristics discussed:
- **Opaque**: True
- **Slightly Alkaline**: True (pH 7.35 - 7.45)
- **Highly Acidic**: False
- **Slightly Alkaline Red Colored**: True (since blood is red and slightly alkaline)
- **Opaque and Slightly Acidic**: False (it is not acidic)

7. **Conclusion**:
- The correct statement about blood is that it is **opaque, red-colored, and slightly alkaline**. Therefore, the true statement from the options provided is that blood is **slightly alkaline**.

### Final Answer:
The true statement for blood is that it is **slightly alkaline**.

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