The number of nephrons present in a human being is about

Options

A. one lakh
B. two lakhs
C. ten lakhs
D. twenty lakhs

Answer

To determine the number of nephrons present in a human being, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Nephrons**: Nephrons are the structural and functional units of the kidney. They play a crucial role in the processes of excretion and osmoregulation.

2. **Components of Nephrons**: Each nephron consists of several parts, including:
- Glomerulus
- Proximal Convoluted Tubule (PCT)
- Loop of Henle
- Distal Convoluted Tubule (DCT)
- Collecting Duct

3. **Estimating the Number of Nephrons**: The question asks for the approximate number of nephrons in a human being. Research indicates that a healthy human kidney contains a significant number of nephrons.

4. **Common Estimates**: It is commonly accepted that a healthy human being has about 1 million to 1.5 million nephrons per kidney. Since humans have two kidneys, the total number of nephrons can be estimated to be around 2 million to 3 million.

5. **Selecting the Correct Answer**: Among the options provided:
- 1 lakh (100,000)
- 2 lakhs (200,000)
- 10 lakhs (1,000,000)
- 20 lakhs (2,000,000)

The most accurate answer is **10 lakhs (1 million)**, which represents the approximate number of nephrons in one kidney.

### Conclusion:
The number of nephrons present in a human being is about **10 lakhs (1 million)**.

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