Which of the following blood vessel in the circulatory system of frog has more deoxygenated blood `:-`

Options

A. Pulmonary artery
B. Precaval veins
C. Pulmocutaneous artery
D. Pulmocutaneous vein

Answer

To determine which blood vessel in the circulatory system of a frog has more deoxygenated blood, we can analyze the options provided:

1. **Pulmonary Artery**: This vessel carries deoxygenated blood from the heart to the lungs for oxygenation. However, it primarily serves the lungs and not the skin.

2. **Precaval Veins**: These veins return deoxygenated blood from the upper body to the heart. While they do carry deoxygenated blood, they are not primarily involved in the exchange of gases.

3. **Pulmonocutaneous Artery**: This artery is unique to amphibians like frogs. It carries deoxygenated blood from the heart to both the lungs and the skin, facilitating cutaneous respiration (breathing through the skin). This means it contains a significant amount of deoxygenated blood.

4. **Pulmocutaneous Vein**: This vein carries oxygenated blood from the lungs and skin back to the heart. Therefore, it contains more oxygenated blood.

Based on this analysis, the blood vessel that has more deoxygenated blood is the **Pulmonocutaneous Artery**.

### Step-by-Step Solution:
1. **Identify the Blood Vessels**: List the options given in the question: Pulmonary artery, Precaval veins, Pulmonocutaneous artery, Pulmocutaneous vein.

2. **Understand the Function of Each Vessel**:
- **Pulmonary Artery**: Carries deoxygenated blood to the lungs.
- **Precaval Veins**: Returns deoxygenated blood from the upper body to the heart.
- **Pulmonocutaneous Artery**: Supplies deoxygenated blood to the lungs and skin for respiration.
- **Pulmocutaneous Vein**: Returns oxygenated blood to the heart.

3. **Analyze the Role of the Pulmonocutaneous Artery**: Recognize that this artery is responsible for supplying blood to the skin (cutaneous respiration) and thus carries a significant amount of deoxygenated blood.

4. **Compare the Amount of Deoxygenated Blood**: Determine which of the vessels carries the most deoxygenated blood. The Pulmonocutaneous Artery is responsible for transporting deoxygenated blood to the skin and lungs.

5. **Conclude the Answer**: Based on the analysis, the vessel with more deoxygenated blood is the **Pulmonocutaneous Artery**.