In this video excerpt from NOVA scienceNOW, correspondent and New York Times technology columnist David Pogue learns how cutting an onion triggers chemical reactions that change the properties of the onion. Animations illustrate how enzymes are separated from other molecules inside the cells of an onion; cutting the onion breaks the barrier and allows the molecules to chemically react and create new molecules. Cutting changes the flavor of the onion and releases molecules that can make you cry.
This video is available in both English and Spanish audio, along with corresponding closed captions.
Visit the program page here.