Understanding Human Blood Circulation

The schematic shows the human circulatory system with four labeled parts. Let's identify each part and its function step by step:

Step 1: Identify the Chambers and Vessels

The heart has four chambers: right atrium (auricle), right ventricle, left atrium (auricle), and left ventricle. Blood vessels connected include:

• Aorta: Largest artery carrying oxygenated blood from the left ventricle to the body.
• Vena Cava: Largest vein carrying deoxygenated blood from the body to the right atrium.
• Pulmonary Artery: Carries deoxygenated blood from the right ventricle to the lungs.
• Pulmonary Vein: Carries oxygenated blood from the lungs to the left atrium.

Step 2: Analyze the Labels in the Diagram

Based on typical schematics:

• (i) Likely Pulmonary Vein (from lungs to left atrium).
• (ii) Likely Pulmonary Artery (from right ventricle to lungs).
• (iii) Likely Aorta (from left ventricle to body).
• (iv) Likely Vena Cava (from body to right atrium).

Step 3: Evaluate the Options

Check each option against correct physiological functions:

1. Option (iii) Aorta - takes blood from heart to body parts. ✅ Correct: Aorta carries oxygenated blood from the left ventricle to the body.
2. Option (iv) Vena cava - takes blood from body parts to the right auricle. ✅ Correct: Vena cava brings deoxygenated blood from the body to the right atrium.
3. Option (ii) Pulmonary artery - takes blood from lung to heart. ❌ Incorrect: Pulmonary artery takes blood FROM heart TO lungs, not from lungs to heart.
4. Option (i) Pulmonary vein - takes impure blood from body part. ❌ Incorrect: Pulmonary vein carries oxygenated (pure) blood from lungs to heart, not impure blood from body.

Step 4: Final Answer

Both options (iii) and (iv) are correct based on standard labeling and functions. However, since the question asks to "identify the correct label," and multiple may be valid, the most precise matches are:

(iii) Aorta - takes blood from heart to body parts. and (iv) Vena cava - takes blood from body parts to the right auricle. are correct statements.

But note: Option (ii) and (i) are incorrect due to reversed/imprecise functions.

Related Topics & Formulae

Key Concepts in Circulation

• Double Circulation: Blood passes through the heart twice per complete cycle (pulmonary and systemic circuits).
• Oxygenation: Lungs oxygenate blood; body tissues deoxygenate it.
• Arteries vs. Veins: Arteries carry blood away from heart (usually oxygenated except pulmonary artery); veins carry blood to heart (usually deoxygenated except pulmonary vein).

Important Formulae

Cardiac Output (CO) = Heart Rate (HR) × Stroke Volume (SV)

Blood Pressure (BP) = Cardiac Output × Peripheral Resistance