Which of the following options represents the pulmonary circulation in human being -

Options

A. `"Left Auricle"overset("Oxygenated")underset("blood")to"Lungs"overset("Deoxygenated")underset("blood")to"Right ventricle"`
B. `"Left Auricle"overset("Deoxygenated")underset("blood")to"Lungs"overset("Oxygenated")underset("blood")to"Right ventricle"`
C. `"Right ventricle"overset("Deoxygenated")underset("blood")to"Lungs"overset("Oxygenated")underset("blood")to"Left Auricle"`
D. `"Right ventricle"overset("Oxygenated")underset("blood")to"Lungs"overset("Deoxygenated")underset("blood")to"Left Auricle"`

Answer

To determine which option represents pulmonary circulation in human beings, we need to understand the pathway of blood flow specifically related to the lungs. Here’s a step-by-step breakdown:

### Step 1: Identify the Starting Point of Pulmonary Circulation
- The pulmonary circulation starts from the **right ventricle** of the heart. This chamber pumps deoxygenated blood into the pulmonary artery.

### Step 2: Understand the Function of the Pulmonary Artery
- The **pulmonary artery** carries deoxygenated blood away from the right ventricle to the lungs. This is a crucial step as it transports blood that is low in oxygen to the site where it can be oxygenated.

### Step 3: Blood Oxygenation in the Lungs
- Once the deoxygenated blood reaches the lungs, it undergoes a process of gas exchange. Here, carbon dioxide is released from the blood, and oxygen is absorbed. This process is essential for replenishing the blood with oxygen.

### Step 4: Identify the Return Pathway to the Heart
- After the blood is oxygenated in the lungs, it is collected by the **pulmonary veins**. These veins carry the now oxygenated blood back to the heart.

### Step 5: Final Destination in the Heart
- The oxygenated blood from the pulmonary veins enters the **left atrium** of the heart. This completes the pulmonary circulation loop, as the blood is now ready to be pumped to the rest of the body.

### Conclusion
- The correct representation of pulmonary circulation includes the right ventricle, pulmonary artery (carrying deoxygenated blood to the lungs), and pulmonary veins (carrying oxygenated blood to the left atrium). Therefore, the best option is **Option 3**: right ventricle → deoxygenated blood to the lungs → oxygenated blood to the left atrium.

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