Refer to the diagram above of the cardiovascular system and explain how blood flows through the heart.

To explain how blood flows through the heart, we will break down the process into clear steps:

1. Blood Entry into the Heart:

   • Deoxygenated blood from the body returns to the heart through two large veins called the superior vena cava and the inferior vena cava.
   • This blood enters the right atrium of the heart.

2. Movement to the Right Ventricle:

   • From the right atrium, blood flows through the tricuspid valve into the right ventricle.

3. Pumping to the Lungs:

   • When the right ventricle contracts, it pumps blood through the pulmonary valve into the pulmonary arteries, leading to the lungs.

4. Oxygenation in the Lungs:

   • In the lungs, carbon dioxide is exchanged for oxygen. The now oxygen-rich blood returns to the heart through the pulmonary veins.

5. Entry into the Left Atrium:

   • This oxygenated blood enters the left atrium of the heart.

6. Movement to the Left Ventricle:

   • Blood then flows through the mitral valve into the left ventricle.

7. Pumping to the Body:

   • When the left ventricle contracts, it pumps the oxygen-rich blood through the aortic valve into the aorta, which distributes it to the rest of the body.

This continuous cycle of blood flow ensures that oxygen is delivered to tissues throughout the body while carbon dioxide is expelled through the lungs.