Fill in the following blanks with suitable words :
Haemoglobin is present in …................. blood cells.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to fill in the blank regarding where hemoglobin is found in the blood.

2. **Identifying Blood Components**: Blood consists of two main components: plasma (the liquid part) and formed elements (the cellular part). The formed elements include three types of cells: red blood cells (RBC), white blood cells (WBC), and platelets.

3. **Focusing on Red Blood Cells**: Among these cells, red blood cells are specifically known for containing hemoglobin. Hemoglobin is an iron-containing protein that is crucial for binding oxygen and transporting it throughout the body.

4. **Conclusion**: Since hemoglobin is present in red blood cells, we can fill in the blank with "red".

**Final Answer**: Haemoglobin is present in **red** blood cells.

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