Question

Answer ASAP 50 points

Answer 1

Answer/Explanation:

In humans, we breathe in oxygen via the respiratory system. The oxygen enters the lungs. The air sacs in the lungs - the alveoli - are the site of gas exchange in the lungs and are where the circulatory and respiratory systems interact.

The alveoli take in the oxygen, where it diffuses into the capillaries (circulatory system). Blood, which passes through the capillaries takes this oxygen to all the cells in the body. Oxygen binds to haemoglobin in red blood cells, which transport it around the body.

Additionally, blood also transports carbon dioxide back to the alveoli of the lungs, where it diffuses into the lungs and is expelled when we breathe out