Transport in Humans (Sec 2)

Which of the following carries blood away from heart?

• Vein

• Artery

• Capillary

• Valve

Answer explanation

Arteries are blood vessels that carry blood away from the heart to the rest of the body. In contrast, veins carry blood back to the heart, capillaries facilitate exchange, and valves prevent backflow.

Which blood vessel carries blood from the lungs to the heart?

• Aorta

• Vena cava

• Pulmonary vein

• Pulmonary artery

Answer explanation

The pulmonary vein is the blood vessel that carries oxygenated blood from the lungs back to the heart, specifically to the left atrium. This is crucial for the heart to pump oxygen-rich blood to the rest of the body.

Blood flows from the vena cava into which chamber of the heart?

• Left atrium

• Right atrium

• Left ventricle

• Right ventricle

Answer explanation

Blood flows from the vena cava into the right atrium, which receives deoxygenated blood from the body before it is pumped to the lungs for oxygenation.

Which kind of blood is carried by the pulmonary veins?

• Oxygenated

• Deoxygenated

Answer explanation

The pulmonary veins carry oxygenated blood from the lungs to the heart. This is in contrast to the pulmonary arteries, which carry deoxygenated blood from the heart to the lungs. Therefore, the correct answer is oxygenated.

Blood flows out of the left ventricle through which of the following blood vessels?

• Aorta

• Vena cava

• Pulmonary artery

• Pulmonary vein

Answer explanation

Blood flows out of the left ventricle through the aorta, which is the main artery that carries oxygenated blood to the body. The vena cava returns deoxygenated blood, while the pulmonary artery and vein are involved in lung circulation.

Which chamber of the heart has the thicker muscular walls?

• Left atrium

• Left ventricle

• Right atrium

• Right ventricle

Answer explanation

The left ventricle has the thickest muscular walls because it needs to pump blood to the entire body, generating high pressure. In contrast, the right ventricle pumps blood to the lungs, requiring less muscular strength.

What is the function of the blood vessel labelled D?

• To transport blood from the heart to the lungs

• To transport blood from the heart to the rest of the body.

• To transport blood from the rest of the body to the heart.

• To transport blood from the lungs to the heart.

Answer explanation

The blood vessel labelled D transports blood from the rest of the body to the heart, returning deoxygenated blood for reoxygenation. This is essential for maintaining circulation and ensuring the heart receives blood to pump again.

What is the function of the blood vessel labelled A?

• To transport blood from the heart to the lungs.

• To transport blood from the heart to the rest of the body.

• To transport blood from the lungs to the heart.

• To transport blood from the rest of the body to the heart.

Answer explanation

The blood vessel labelled A transports blood from the heart to the rest of the body, delivering oxygen and nutrients to tissues. This is a key function of arteries, specifically the aorta.

Which side of the heart has oxygenated blood?

• Top

• Bottom

• Left

• Right

Answer explanation

The left side of the heart contains oxygenated blood, which is pumped to the body. In contrast, the right side receives deoxygenated blood from the body and sends it to the lungs for oxygenation.

Which of the following is NOT true about plasma?

• Consist mainly of water

• Pale yellow liquid

• Transport blood

• Transport waste materials

Answer explanation

Plasma does not transport blood; it is a component of blood. Plasma is the liquid part that carries cells and waste, but it itself is not responsible for transporting blood.