What is the function of the alveoli?give off CO2 from bloodneither of theseBoth take in O2 from air and give off CO2 from bloodtake in O2 from the air

The function of the alveoli is to both take in O2 from air and give off CO2 from blood.

Here's a step-by-step explanation:

1. When we breathe in, air fills our lungs and reaches the alveoli.

2. The walls of the alveoli are very thin and have a lot of tiny blood vessels called capillaries.

3. Oxygen from the air we breathe in passes through the walls of the alveoli and into the blood in the capillaries. This process is called oxygenation.

4. At the same time, carbon dioxide, a waste product from our body's metabolism, passes from the blood in the capillaries into the alveoli. This process is called deoxygenation.

5. When we breathe out, the carbon dioxide is expelled from our body.

So, the alveoli play a crucial role in respiration by exchanging oxygen and carbon dioxide between our lungs and blood.