One of these substances called TE additionally chelates magnesium ions, making it ideal for storing DNA. Britton and Robinson name a “universal” one of these substances. (15[1])Citrate and phosphate are found in one of these (15[1])substances named for McIlvaine, which is mixed with glycerol to create mounting medium. CAPS, MOPS, and HEPES are three in a series of twenty of these agents used in biology named for Norman (*) Good, most of which are zwitterionic compounds. The bicarbonate system in blood acts as one of these (10[1])agents. The capacity of these agents is highest when their pH equals their pKa, which is a consequence of the Henderson-Hasselbalch equation. For 10 points, name these solutions that usually consist of an acid and its conjugate base to keep pH constant. ■END■