When oxygen poor blood leaves the heart, it goes to the __________ to get oxygen
When oxygen-poor blood leaves the heart, it goes to the lungs to get oxygen.
When oxygen-poor blood leaves the heart, it goes to the lungs to get oxygen. To understand why, let's go through the circulatory system step by step:
1. The heart is a muscular organ that pumps blood throughout the body. It has four chambers: two atria (left and right) and two ventricles (left and right).
2. Deoxygenated blood, which has been depleted of oxygen and high in carbon dioxide, enters the right atrium of the heart from the body through the superior and inferior vena cava veins.
3. From the right atrium, the blood flows into the right ventricle. The right ventricle contracts, pumping the oxygen-poor blood out of the heart through the pulmonary artery.
4. The pulmonary artery splits into two branches, with one going to each lung. Within the lungs, the pulmonary artery branches out into a network of smaller blood vessels called pulmonary capillaries.
5. In the pulmonary capillaries, the oxygen-poor blood comes into close proximity with the alveoli, which are tiny air sacs in the lungs. The alveoli are surrounded by a rich network of blood vessels, ensuring efficient gas exchange.
6. Oxygen from the inhaled air enters the alveoli and passes through the thin walls of the capillaries. At the same time, carbon dioxide from the blood diffuses into the alveoli to be exhaled.
7. The oxygen molecules bind to a protein in red blood cells called hemoglobin. As a result, the deoxygenated blood turns into oxygenated blood.
8. Once the blood has picked up oxygen in the pulmonary capillaries, it leaves the lungs through the pulmonary veins and returns to the heart. This oxygenated blood enters the left atrium of the heart.
From here, the oxygenated blood will be pumped by the left ventricle to supply oxygen to the rest of the body through the systemic circulation. Meanwhile, the process of deoxygenated blood getting oxygen in the lungs starts again.
So, to summarize, when oxygen-poor blood leaves the heart, it goes to the lungs through the pulmonary artery to get oxygen in the pulmonary capillaries.