Cell Energy - Bubbling Yeast

Middle schoolers identify that yeast are a single celled fungi that are a great model organism for studying respiration in the classroom. They also fill the bulb of a disposable pipet (eyedropper) with yeast, then submerge the pipet in a test tube of water. Students then measure the rate of respiration by counting the number of bubbles of carbon dioxide gas that emerge from the tip of the pipet in a certain length of time.