Anatomy: Animals Inside


What is respiration?

Respiration is the exchange of gases (oxygen and carbon dioxide) between an animal and its environment. The three phases to the process of respiration (gas exchange) are 1) breathing, when an animal inhales oxygen and exhales carbon dioxide; 2) transport of gases via the blood (circulatory system) to the body’s tissues; and 3) at the cellular level, when the cells take in oxygen from the blood and, in return, add carbon dioxide to the blood. Different types of animals have different respiratory organs for gas exchange, with the four types of respiratory organs being the skin, gills, tracheae, and lungs.


This is a web preview of the "The Handy Biology Answer Book" app. Many features only work on your mobile device. If you like what you see, we hope you will consider buying. Get the App