Which of the following statements is correct?

Options

A. Peripheral circulation is the flow of deoxygenated blood from the right ventricle to the lungs and return of oxygenated blood from the lungs to the left atrium.
B. Pulmonary circulation carries deoxygenated blood from pulmonary and bronchial arteries.
C. Hepatic portal system is a unique vascular connection which exists between digestive tract and heart.
D. Coronary circulation is the flow of oxygenated blood from ascending aorta to heart muscle and return of deoxygenated blood from heart muscle to the right atrium.

Answer

To determine which statement is correct, let's analyze each option step by step:

### Step 1: Analyze Option 1
**Statement:** Peripheral circulation is the flow of deoxygenated blood from the right ventricle to the lungs and returns oxygenated blood from the lungs to the left atrium.

**Analysis:** This statement describes pulmonary circulation, not peripheral circulation. In pulmonary circulation, deoxygenated blood flows from the right ventricle to the lungs via the pulmonary artery, and oxygenated blood returns to the left atrium through the pulmonary veins. Therefore, this statement is incorrect.

### Step 2: Analyze Option 2
**Statement:** Pulmonary circulation carries deoxygenated flow from the pulmonary and bronchial artery.

**Analysis:** This statement is incorrect because pulmonary circulation specifically involves the pulmonary artery carrying deoxygenated blood to the lungs. The bronchial arteries supply oxygenated blood to the lungs, not deoxygenated blood. Thus, this statement is also incorrect.

### Step 3: Analyze Option 3
**Statement:** Hepatic portal system is a unique vascular connection which exists between the digestive tract and heart.

**Analysis:** This statement is incorrect. The hepatic portal system connects the digestive tract to the liver, not directly to the heart. It allows nutrient-rich blood from the digestive organs to be processed by the liver before returning to the systemic circulation. Therefore, this statement is incorrect.

### Step 4: Analyze Option 4
**Statement:** Coronary circulation is the flow of oxygenated blood.

**Analysis:** This statement is correct. Coronary circulation refers to the flow of oxygenated blood from the ascending aorta to the heart muscle via the coronary arteries. The deoxygenated blood from the heart muscle is then returned to the right atrium. Thus, this statement is accurate.

### Conclusion
Based on the analysis of each option, the correct answer is **Option 4**: Coronary circulation is the flow of oxygenated blood.

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