Fill in the following blanks with suitable words :
Our heart has ….................. chambers .

Answer

**Step-by-Step Solution:**

1. **Identify the Subject**: The question is about the human heart and its structure.

2. **Understand the Structure of the Heart**: The human heart is a muscular organ that is part of the circulatory system. It is responsible for pumping blood throughout the body.

3. **Recall the Number of Chambers**: In humans, the heart consists of four chambers. These chambers are categorized into atria and ventricles.

4. **Specify the Chambers**: The human heart has:
- 2 Atria (the upper chambers)
- 2 Ventricles (the lower chambers)

5. **Fill in the Blank**: Therefore, the complete sentence would be: "Our heart has **four** chambers."

**Final Answer**: Our heart has **four** chambers.

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