Which of the following represents systemic circulation ?

Options

A. Left atrium `to` Lungs `to` Right atrium
B. Right atrium `to` Lungs `to` Right ventricle
C. Left ventricle `to` Body parts `to` Right atrium
D. Right ventricle `to` Body parts `to` left atrium

Answer

**Step-by-Step Solution:**

1. **Understanding Circulation Types**: The human circulatory system consists of two main types of circulation: pulmonary circulation and systemic circulation.

2. **Defining Pulmonary Circulation**: Pulmonary circulation refers to the movement of deoxygenated blood from the right side of the heart to the lungs, where it gets oxygenated, and then back to the left side of the heart.

3. **Defining Systemic Circulation**: Systemic circulation is the process where oxygenated blood is pumped from the left side of the heart to the rest of the body and then returns deoxygenated blood back to the right side of the heart.

4. **Identifying the Pathway**:
- Oxygenated blood enters the left atrium from the lungs via the pulmonary veins.
- It then moves into the left ventricle, which pumps it out through the aorta to the body.
- The deoxygenated blood returns to the heart through the vena cava into the right atrium.

5. **Conclusion**: Therefore, systemic circulation represents the flow of blood from the left ventricle to the body parts and back to the right atrium.

**Final Answer**: The systemic circulation is represented by the pathway from the left ventricle to the body and then to the right atrium.

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