A chamber containing small living things such as crickets, worms, or
germinating seeds
A terrarium of plants undergoing respiration and photosynthesis cycles
A classroom
An enclosed atmosphere containing sodium hydroxide or potassium hydroxide
as CO2 scavengers
The chemical reaction between hydrochloric acid and sodium bicarbonate
Carbon dioxide gas diffusing through a gas diffusion tube
Fermentation or respiration of sugars
Human respiration under various conditions (at rest vs. after exercise)