Answer :
Answer:
Oxygen and carbon dioxide, dissolved in water, are exchanged by diffusion in the lungs:
- oxygen moves down a concentration gradient from the air in the alveoli to the blood.
- carbon dioxide moves down a concentration gradient from the blood to the air in the alveoli.
Answer:
oxygen moves down a concentration gradient from the air in the alveoli to the blood.
carbon dioxide moves down a concentration gradient from the blood to the air in the alveoli.
Explanation: