Question 1:

Which chamber of the heart receives oxygenated blood from the lungs?

Explanation: The left atrium receives oxygenated blood from the lungs through the pulmonary veins.

Question 2:

What is the function of the heart valves?

Explanation: The heart valves ensure one-way blood flow and prevent the backflow of blood between the chambers of the heart.

Question 3:

Which of the following is responsible for initiating the electrical signals that regulate the heart's contractions?

Explanation: The sinoatrial (SA) node, often referred to as the heart's natural pacemaker, is responsible for initiating the electrical signals that regulate the heart's contractions.

Question 4:

Which blood vessels carry oxygenated blood away from the heart?

Explanation: Arteries carry oxygenated blood away from the heart to various parts of the body.

Question 5:

Which of the following is the correct sequence of blood flow through the heart?

Explanation: The correct sequence of blood flow through the heart is: Right atrium → Right ventricle → Pulmonary arteries → Lungs → Pulmonary veins → Left atrium → Left ventricle.