Normal range of urea in 100 ml of human blood is

Options

A. (a) `56 - 70mg`
B. (b) `40 - 80 mg`
C. (c) `17 - 30 mg`
D. (d) `4 - 16 mg`

Answer

To determine the normal range of urea in 100 ml of human blood, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the normal range of urea concentration in human blood measured in mg per 100 ml.

2. **Review the Options**: The options provided are:
- a) 56 to 70 mg
- b) 40 to 80 mg
- c) 17 to 30 mg
- d) 4 to 16 mg

3. **Recall Biological Knowledge**: Urea is a waste product formed from the breakdown of proteins and is primarily excreted through urine. The kidneys filter blood to remove excess urea.

4. **Identify Normal Urea Levels**: Based on biological standards, the normal concentration of urea in human blood typically ranges from 17 to 30 mg per 100 ml.

5. **Evaluate the Options**:
- Option a (56 to 70 mg) is too high.
- Option b (40 to 80 mg) is also too high.
- Option c (17 to 30 mg) falls within the normal range.
- Option d (4 to 16 mg) is too low.

6. **Select the Correct Answer**: Based on the evaluation, the correct answer is option c) 17 to 30 mg.

### Final Answer:
The normal range of urea in 100 ml of human blood is **17 to 30 mg**.

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