Lungs inside the body provide surfaces which can be kept moist by fluids in the blood. The lungs are enclosed in the body, which helps to keep them from drying out. They are protected from wind and sudden temperature changes. The lungs are rich in blood vessels so that they can absorb as much oxygen as possible. The lungs also give up carbon dioxide.
Carbon dioxide builds up in the body as a waste product of metabolism.
If there is too much of it in the body, the organism will die. Elizabeth Anne Viau and her licensors. All rights reserved. This material may be used by individuals for instructional purposes but not sold.