What is the path of blood through the heart starting at the right atrium?

What is the path of blood through the heart starting at the right atrium?

• A. Right atrium → tricuspid valve → right ventricle → pulmonary valve → pulmonary arteries → lungs → pulmonary veins → left atrium → mitral valve → left ventricle → aortic valve → aorta
• B. Right atrium → bicuspid valve → left ventricle → aorta
• C. Right atrium → tricuspid valve → left ventricle → pulmonary valve
• D. Right atrium → pulmonary valve → right ventricle

Answer: (A)

The main idea being tested is the correct sequence of blood flow through the heart, including which valves and chambers it passes in order to move from deoxygenated blood to oxygenated blood and then to the body. Blood starts in the right atrium, where deoxygenated blood returning from the body collects. It then flows through the tricuspid valve into the right ventricle. From the right ventricle, blood is pumped through the pulmonary valve into the pulmonary arteries and to the lungs for oxygenation. After picking up oxygen, the blood returns via the pulmonary veins into the left atrium. It passes through the mitral valve into the left ventricle, and from there goes through the aortic valve into the aorta to supply the body. This route is correct because it preserves the one-way flow of blood, includes the correct sequence of chambers and valves, and follows the two circulatory circuits: pulmonary (to the lungs) and systemic (to the rest of the body). Other sequences either skip the lungs, misplace valves, or move between chambers in a way that doesn’t reflect actual anatomy—for example, routing blood from the right atrium directly to the left ventricle or using incorrect valves between chambers.

The main idea being tested is the correct sequence of blood flow through the heart, including which valves and chambers it passes in order to move from deoxygenated blood to oxygenated blood and then to the body.

Blood starts in the right atrium, where deoxygenated blood returning from the body collects. It then flows through the tricuspid valve into the right ventricle. From the right ventricle, blood is pumped through the pulmonary valve into the pulmonary arteries and to the lungs for oxygenation. After picking up oxygen, the blood returns via the pulmonary veins into the left atrium. It passes through the mitral valve into the left ventricle, and from there goes through the aortic valve into the aorta to supply the body.

This route is correct because it preserves the one-way flow of blood, includes the correct sequence of chambers and valves, and follows the two circulatory circuits: pulmonary (to the lungs) and systemic (to the rest of the body).

Other sequences either skip the lungs, misplace valves, or move between chambers in a way that doesn’t reflect actual anatomy—for example, routing blood from the right atrium directly to the left ventricle or using incorrect valves between chambers.