Which side of the heart (left or right) has :
carbon dioxide rich blood?

Answer

To answer the question of which side of the heart has carbon dioxide-rich blood, we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding the Heart Structure**: The heart has four chambers: the right atrium, right ventricle, left atrium, and left ventricle.

2. **Identifying Blood Flow**: Blood flows through the heart in a specific manner. Blood that is returning from the body is low in oxygen and high in carbon dioxide (this is known as deoxygenated blood).

3. **Right Side of the Heart**: The deoxygenated blood enters the heart through two large veins: the superior vena cava and the inferior vena cava. This blood enters the right atrium.

4. **Movement to the Right Ventricle**: From the right atrium, the deoxygenated blood moves into the right ventricle through the tricuspid valve.

5. **Conclusion**: Therefore, the right side of the heart (specifically the right atrium and right ventricle) contains carbon dioxide-rich blood.

### Final Answer:
The right side of the heart has carbon dioxide-rich blood.

---