Select the correct match between different formed elements of blood and their respective features in man

Options

A. Erythrocytes occur in millions
B. leucocytes contain hemoglobin
C. Platelets are called thromboblasts
D. all leucocytes have granular cytoplasm

Answer

To solve the question of matching the formed elements of blood with their respective features in humans, we will analyze each type of formed element and its characteristics step by step.

### Step-by-Step Solution:

1. **Identify the Formed Elements of Blood:**
- The formed elements of blood include:
- Red Blood Cells (RBCs) or Erythrocytes
- White Blood Cells (WBCs) or Leukocytes
- Platelets or Thrombocytes

2. **Understand the Features of Each Element:**
- **Red Blood Cells (RBCs):**
- They are responsible for transporting oxygen and carbon dioxide.
- They contain hemoglobin, which gives them a red color.
- The normal count is approximately 4.5 to 5.5 million RBCs per cubic millimeter (cmm) of blood.

- **White Blood Cells (WBCs):**
- They are involved in the immune response and defense mechanisms of the body.
- They do not contain hemoglobin and are colorless.
- WBCs can be classified into two types:
- Granulocytes (e.g., neutrophils, eosinophils, basophils)
- Agranulocytes (e.g., lymphocytes, monocytes)

- **Platelets:**
- They play a crucial role in blood clotting.
- They are derived from larger cells called megakaryocytes, not thromboblasts.
- The normal count is approximately 150,000 to 300,000 platelets per cmm of blood.

3. **Match Each Element with Its Feature:**
- **Erythrocytes:** Occur in millions (4.5 to 5.5 million per cmm) – **Correct Match**
- **Leukocytes:** Do not contain hemoglobin – **Correct Feature**
- **Platelets:** Are called thrombocytes, not thromboblasts – **Incorrect Match**
- **Leukocytes:** Not all have granulocytoplasm (some are agranular) – **Incorrect Match**

4. **Select the Correct Match:**
- The only correct match is for Erythrocytes, which occur in millions.

### Conclusion:
The correct answer is that erythrocytes (RBCs) occur in millions, making option 1 the correct choice.

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