For the answers to these questions and more, we're serving up two Bytesize videos that celebrate the chemistry of Thanksgiving. The first video in the series debunks the long-held holiday myth that a compound in turkey known as tryptophan makes people especially drowsy after a Thanksgiving meal. The other video features an entertaining holiday lecture from Diane Bunce, Ph.D., professor of chemistry at The Catholic University of America and recipient of the ACS Helen Free Award for Public Outreach.

The history of photography is rich with chemical innovations and insights, producing hundreds of different processes to develop images in unique and often beautiful ways. But these historical images can be difficult to conserve, especially since each type of photograph requires a different preservation technique. While two photos could look very similar, they may differ chemically in dramatic ways.

This is where photo conservation scientists like Art Kaplan at the Getty Conservation Institute come into the picture. Art spends his days studying different styles of photographs, their materials and the chemistry that gave life to still life in the early days of photography. His office is loaded with drawers of photographic samples, scientific instruments and a clear passion for frozen history. In our latest video, Art explains the developmental processes of several types of photographs including daguerreotypes, ambrotypes and tintypes.