Question

What is the correct order of blood flow in the heart?

1) Oxygen-poor blood enters the right atrium, passes through the tricuspid valve into the right ventricle, then through the pulmonary valve into the pulmonary artery.
2) Oxygen-poor blood enters the left atrium, passes through the mitral valve into the left ventricle, then through the aortic valve into the aorta.
3) Oxygen-rich blood enters the right atrium, passes through the tricuspid valve into the right ventricle, then through the pulmonary valve into the pulmonary artery.
4) Oxygen-rich blood enters the left atrium, passes through the mitral valve into the left ventricle, then through the aortic valve into the aorta.

Answer 1

The correct order of blood flow in the heart is option 1 for the right side, where oxygen-poor blood is pumped from the right atrium through to the pulmonary artery, and option 4 for the left side, where oxygen-rich blood is pumped from the left atrium through to the aorta.

Step-by-step explanation:

The correct order of blood flow in the heart begins when oxygen-poor blood enters the right atrium from the body through the superior and inferior vena cava. This blood then passes through the tricuspid valve into the right ventricle, and from there it is pumped through the pulmonary valve into the pulmonary artery and on to the lungs to be oxygenated. Once oxygen-rich, the blood returns to the heart, entering the left atrium via the pulmonary veins. It then moves through the mitral valve into the left ventricle. Finally, it is pumped through the aortic valve into the aorta to be distributed throughout the body. Therefore, the correct sequence from the options provided is 1) for the right side of the heart and then 4) for the left side, illustrating the dual circulation of the heart.