Blood Composition Changes in the Lungs: Oxygenation & CO2 Removal

In the lungs, blood undergoes key compositional changes:

1. Oxygenation: O₂ diffuses from alveoli into blood, converting deoxygenated to oxygenated blood.
2. CO₂ removal: Metabolic waste CO₂ diffuses from blood into alveoli for exhalation.
3. pH balance: CO₂ removal prevents acidosis; lungs regulate blood pH.
4. Gas exchange: Diffusion across alveolar-capillary membranes ensures O₂ supply and CO₂ elimination.
5. Hemoglobin binding: O₂ binds hemoglobin forming oxyhemoglobin for systemic transport.

These changes maintain O₂/CO₂ balance and homeostasis.