Understanding Heart Anatomy and Function

Which vessel returns blood to the heart from the head and arms?

• Inferior vena cava

• Superior vena cava

• Pulmonary veins

• Aorta

Answer explanation

The superior vena cava is the vessel that returns deoxygenated blood from the head, neck, and arms to the heart, specifically to the right atrium. The inferior vena cava serves the lower body, while the pulmonary veins and aorta have different functions.

Where does deoxygenated blood enter the heart?

• Left atrium

• Right atrium

• Left ventricle

• Right ventricle

Answer explanation

Deoxygenated blood enters the heart through the right atrium. It collects blood returning from the body via the superior and inferior vena cavae before being pumped to the right ventricle for pulmonary circulation.

What is the function of the tricuspid valve?

• It pumps blood to the lungs

• It is the right atrioventricular valve

• It sends oxygenated blood back to the heart

• It keeps blood from flowing back into the left ventricle

Answer explanation

The tricuspid valve is the right atrioventricular valve, located between the right atrium and right ventricle. It ensures blood flows from the atrium to the ventricle without backflow, making the correct choice about its function.

Which chamber of the heart pumps blood to the lungs?

• Left atrium

• Right atrium

• Left ventricle

• Right ventricle

Answer explanation

The right ventricle is responsible for pumping deoxygenated blood to the lungs for oxygenation. The left atrium receives oxygenated blood from the lungs, while the left ventricle pumps it to the body.

What is the role of the pulmonary arteries?

• They send deoxygenated blood to the lungs

• They send oxygenated blood back to the heart

• They carry blood away from the heart to the rest of the body

• They return blood to the heart from the trunk and legs

Answer explanation

The pulmonary arteries are responsible for transporting deoxygenated blood from the heart to the lungs, where it can receive oxygen. This makes the correct choice "They send deoxygenated blood to the lungs."

Which valve leads to the lungs?

• Mitral valve

• Tricuspid valve

• Pulmonary semilunar valve

• Aortic semilunar valve

Answer explanation

The pulmonary semilunar valve is responsible for directing blood from the right ventricle to the lungs for oxygenation. The other valves listed do not lead to the lungs.

Which chamber receives blood from the lungs?

• Right atrium

• Left atrium

• Right ventricle

• Left ventricle

Answer explanation

The left atrium receives oxygenated blood from the lungs via the pulmonary veins, while the right atrium receives deoxygenated blood from the body. Therefore, the correct answer is the left atrium.

What is the function of the aortic semilunar valve?

• It pumps blood to the lungs

• It keeps blood from flowing back into the left ventricle

• It is the right atrioventricular valve

• It sends deoxygenated blood to the lungs

Answer explanation

The aortic semilunar valve prevents blood from flowing back into the left ventricle after it has been pumped into the aorta, ensuring unidirectional blood flow from the heart to the body.

Through which vessel does blood leave the heart to be pumped to the rest of the body?

• Pulmonary veins

• Superior vena cava

• Aorta

• Inferior vena cava

Answer explanation

Blood leaves the heart through the aorta, which is the main artery that distributes oxygenated blood to the rest of the body. The pulmonary veins carry blood to the heart, while the superior and inferior vena cava return deoxygenated blood.

Which part of the heart is the most inferior part of the external heart?

• Base of heart

• Apex of heart

• Right atrium

• Left ventricle

Answer explanation

The apex of the heart is the most inferior part of the external heart, located at the bottom tip, while the base is at the top. The right atrium and left ventricle are not the most inferior parts.