Which one of the following statements about erythrocytes is false ?

Options

A. In the life cycle of a foetus, erythropoiesis takes place in both liver and bone marrow.
B. They maintain the viscosity of blood.
C. They maintain blood pH as thy contain haemoglobin which acts as a buffer.
D. The total quantity of RBCs in a human male body is around 5.5 million.

Answer

To determine which statement about erythrocytes (red blood cells) is false, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Erythrocytes**:
- Erythrocytes, commonly known as red blood cells (RBCs), are responsible for transporting oxygen and carbon dioxide in the body. They contain hemoglobin, an iron-containing protein that binds oxygen.

2. **Analyzing the Statements**:
- **Statement A**: "In the life of a fetus, erythropoiesis occurs in both liver and bone marrow."
- This statement is **true**. In fetuses, red blood cells are produced in both the liver and the bone marrow.

- **Statement B**: "It maintains the viscosity of blood."
- This statement is also **true**. RBCs contribute to the viscosity of blood, which is crucial for proper circulation.

- **Statement C**: "It maintains the pH of the blood."
- This statement is **true** as well. Hemoglobin acts as a buffer, helping to maintain the pH of blood by managing the levels of carbon dioxide and bicarbonate.

- **Statement D**: "In a human male, the total quantity of RBCs is 5.5 million."
- This statement is **false**. The figure refers to the number of RBCs per cubic millimeter (mm³) of blood, not the total quantity in the body. The normal range for RBCs in a healthy adult male is approximately 4.5 to 6 million per mm³, not as a total count.

3. **Conclusion**:
- The false statement regarding erythrocytes is **Statement D**.