Question

External respiration involves the exchange of ________.

1) wastes through the skin
2) nutrients in the lungs
3) O₂ and CO₂ between the lungs and the environment
4) O₂ and CO₂ within the cells

Answer 1

External respiration involves the exchange of O₂ and CO₂ between the lungs and the environment.

Step-by-step explanation:

External respiration involves the exchange of O₂ and CO₂ between the lungs and the environment.

Respiration is the process in which oxygen moves from the outside air into the body and carbon dioxide and other waste gases move from inside the body into the outside air.

This exchange of gases occurs in the alveoli of the lungs during external respiration.