Eumelanin has two forms linked to 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA). DHI-derived eumelanin is dark brown or black and insoluble, and DHICA-derived eumelanin which is lighter and soluble in alkali. Both eumelanins arise from the oxidation of tyrosine in specialized organelles called melanosomes. This reaction is catalyzed by the enzyme tyrosinase. The initial product, dopaquinone can transform into either 5,6-dihydroxyindole (DHI) or 5,6-dihydroxyindole-2-carboxylic acid (DHICA). DHI and DHICA are oxidized and then polymerize to form the two eumelanins.[6]Furthermore, "In natural conditions, DHI and DHICA often co-polymerize, resulting in a range of eumelanin polymers." Are you still awake? Because I nodded off out of boredom/bewilderment sometime around "the oxidation of tyrosine." Stuff like this is exactly why I had to cheat and charm my way into a C that I didn't deserve. That's when I did a double-take on Professor Johnson's position at Rice. It took a minute to sink in, but despite Johnson's doctorate in chemistry, she doesn't work in Rice's renowned chemistry department. Johnson works in the university's DEI department. In Chem 125, Johnson will instruct her undergrads — who are expected to pony up around $78,278 for the privilege of attending during the 2022-23 academic year — on how to "apply chemical tools and analysis to understand black life in the US," along with her "personal reflections and proposals for addressing inequities in chemistry and chemical education." In other words, Tom Lehrer can teach you more about chemistry for free in 85 seconds than Professor Johnson can for thousands of dollars over an entire semester. But forget all that sciencey stuff. "What does it look like to do science on one's own terms?" is a question raised in the flyer promoting Chem 125. Another is, "What does justice look like in chemistry?" And you thought Johnson would teach quaint chemistry principles like covalent bonding or the atomic structures of the known elements? Chem 125 is not a chemistry class. Rice — which, with its reputation as a serious research school, ought to know better — should have named Johnson's class Agitprop 101. Read more at: PJMedia.com
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