An animal requires air for survival, and air is primarily oxygen and nitrogen. Given these facts, what does an animal require for survival among the following options:
- layer of body fat under skin
 - A compound that donates proton
 - Molecular kinetic energy
 - mineral particles and organics
 - a complete digestive system
 - converting food to energy
 - keeping food fresh for long periods of time
 - Something made primarily of oxygen and nitrogen


 

        Something made primarily of oxygen and nitrogen 