Blood Vessels (Arteries, Capillaries, and Veins)

Which type of blood vessel carries oxygen-rich (oxygenated) blood away from the heart?

• Pulmonary vein

• Capillaries

• Veins

• Arteries

Answer explanation

Arteries are the blood vessels that carry oxygen-rich blood away from the heart to the rest of the body. In contrast, veins carry deoxygenated blood back to the heart, and capillaries are the sites of gas exchange.

Which type of blood vessel carries oxygen-poor (deoxygenated) back to the heart specifically through the superior vena cava and inferior vena cava for reoxygenation?

• Pulmonary vein

• Capillaries

• Veins

• Arteries

Answer explanation

Veins are the blood vessels that carry oxygen-poor blood back to the heart. The superior and inferior vena cava are major veins that transport deoxygenated blood for reoxygenation in the heart.

Which vessel carries oxygen-poor blood (deoxygenated) from the heart to the lungs?

• Superior vena cava

• Pulmonary artery

• Aorta

• Pulmonary vein

Answer explanation

The pulmonary artery is the vessel that carries deoxygenated blood from the heart to the lungs for oxygenation, making it the correct choice. The other options either carry oxygenated blood or return blood to the heart.

Which blood vessel returns oxygen-rich (oxygenated) blood from the lungs to the heart?

• Pulmonary artery

• Pulmonary vein

• Aorta

• Inferior vena cava

Answer explanation

The pulmonary vein is responsible for returning oxygen-rich blood from the lungs to the heart, while the pulmonary artery carries deoxygenated blood from the heart to the lungs. The aorta and inferior vena cava serve different functions.

What is the primary function of capillaries in the circulatory system?

• Exchange of gases and nutrients

• Transport blood to the heart

• Regulate blood pressure

• Store blood

Answer explanation

The primary function of capillaries is the exchange of gases and nutrients between blood and tissues. They are the smallest blood vessels, allowing for efficient transfer of oxygen, carbon dioxide, and essential nutrients.