Number of lymphocytes present in a healthy human is

Options

A. 1 trillion
B. 100 billion
C. 10 trillion
D. 100 trillion

Answer

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

### Step-by-Step Solution:

1. **Understand Lymphocytes**: Lymphocytes are a type of white blood cell that play a crucial role in the immune system. They include T cells, B cells, and natural killer cells.

2. **Identify the Role of Lymphocytes**:
- T cells are involved in cell-mediated immunity.
- B cells are responsible for humoral immunity, producing antibodies.
- Natural killer cells are part of the innate immune response.

3. **Research the Normal Count**: The normal range of lymphocytes in a healthy human is typically measured in trillions.

4. **Estimate the Total Number**: Based on medical literature, the total number of lymphocytes in a healthy adult human is approximately 1 trillion.

5. **Select the Correct Answer**: Given the options of 1 trillion, 10 trillion, and 100 trillion, the correct answer is 1 trillion.

### Final Answer:
The number of lymphocytes present in a healthy human is approximately **1 trillion**.

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