Normal range of urea in 100 ml of human blood is

Options

A. `56 - 70mg`
B. `40 - 80 mg`
C. `17 - 30 mg`
D. `4 - 16 mg`

Answer

### Step-by-Step Solution:

1. **Understanding Urea Production**: Urea is produced in the liver as a byproduct of protein metabolism. When proteins are broken down, they release nitrogen, which is converted into urea through the urea cycle.

2. **Normal Range of Urea**: The normal concentration of urea in human blood is typically measured in milligrams per deciliter (mg/dL).

3. **Identifying the Normal Range**: For a healthy adult, the normal range of urea in the blood is approximately 7 to 20 mg/dL. This range can vary slightly depending on individual laboratories and their reference standards.

4. **Conversion to 100 mL**: Since the question asks for the normal range of urea in 100 mL of blood, we need to convert the range from mg/dL to mg/100 mL.
- 1 dL = 100 mL, so the range remains the same: 7 to 20 mg/dL is equivalent to 7 to 20 mg in 100 mL of blood.

5. **Conclusion**: Therefore, the normal range of urea in 100 mL of human blood is between 7 mg and 20 mg.

### Final Answer:
The normal range of urea in 100 mL of human blood is **7 to 20 mg**.

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