Vena cava drain the blood into the _________ atrium while pulmonary veins drain the blood into the _____

Explanation

To answer the question, we need to identify where the vena cava and pulmonary veins drain blood in the heart.

### Step-by-Step Solution:

1. **Understand the Role of the Vena Cava**:
- The vena cava consists of two large veins: the superior vena cava and the inferior vena cava.
- These veins are responsible for carrying deoxygenated blood from the body back to the heart.

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