What kind of blood is present in right atrium (auricle)?

Explanation

### Step-by-Step Solution:

1. **Understanding the Heart Structure**: The heart consists of four chambers: two atria (upper chambers) and two ventricles (lower chambers). The right atrium (or auricle) is one of these upper chambers.

2. **Blood Flow into the Right Atrium**: Blood from the body, which is low in oxygen (deoxygenated blood), returns to the heart through large veins known as the vena cava. This blood enters the right atrium.

3. **Nature of Blood in the Right Atrium**: Since the right atrium receives blood from the body via the vena cava, the blood present in this chamber is deoxygenated. This means it has a lower concentration of oxygen and a higher concentration of carbon dioxide.

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