Question

The WBC count of a person's blood sample is 8000/cu.mm. How many eosinophils and lymphocytes would be in the same blood sample approximately ?

• A. 300 - 500/cu.mm and 500 - 700/cu.mm, respectively
• B. 300 - 500/cu.mm and 1200 - 1500/cu.mm, respectively
• C. 100 - 120/cu.mm and 160 - 200/cu.mm, respectively
• D. 160 - 240/cu.mm and 1600 - 2000/cu.mm, respectively

Hint:

Logic Tip: Use the mnemonic \textbf{N}ever \textbf{L}et \textbf{M}onkeys \textbf{E}at \textbf{B}ananas to remember the order of abundance: Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils.

Answer 1

The Correct Option is D

Step 1 : Understanding the Question:
The objective is to calculate the absolute count of specific white blood cell types (eosinophils and lymphocytes) given the total WBC count. This requires knowledge of the standard percentages (DLC) of these cells in healthy human blood.
Step 2 : Key Formulas and Approach:
1. Recall standard percentages: Lymphocytes (20-25%) and Eosinophils (2-3%).
2. Formula: Absolute count = (Standard % / 100) $\times$ Total WBC count.
3. Apply this to the given total of 8000/cu.mm.
Step 3 : Detailed Explanation:

Calculating Eosinophils:
Normal range for eosinophils is 2% to 3% of the total leukocyte count.

Lower bound = $2% \text{ of } 8000 = (2 / 100) \times 8000 = 160$.

Upper bound = $3% \text{ of } 8000 = (3 / 100) \times 8000 = 240$.

Therefore, the count is 160 - 240 / cu.mm.


Calculating Lymphocytes:
Normal range for lymphocytes is 20% to 25% of the total leukocyte count.

Lower bound = $20% \text{ of } 8000 = (20 / 100) \times 8000 = 1600$.

Upper bound = $25% \text{ of } 8000 = (25 / 100) \times 8000 = 2000$.

Therefore, the count is 1600 - 2000 / cu.mm.


Step 4 : Final Answer:
The calculated ranges for eosinophils (160-240) and lymphocytes (1600-2000) match the data provided in option (D).