You Browse through
the Laboratory's Reference Books

"Hey, here's a book that explains the atomic absorption flame photometer," Zack says. "It's used for detecting poison -- well, some poisons, anyway. Many poisons have metal salts in them, like sodium in sodium cyanide. Metal salts give off a distinctive color when burned. So a substance laced with sodium cyanide would have a stronger readout of sodium than normal."

"I found out something about microbe sizes," you say, hefting a big microbiology text. "Funguses, or fungi, or whatever, are many-celled creatures that are generally larger than 10 microns. Bacteria are one-celled creatures and they're between a half-micron and 10 microns in size. Viruses are way smaller than bacteria. Both viruses and chemicals would pass right through a half-micron filter."

"I told you already, it's not a virus," Zack says pointedly. "So don't waste your time reading about them."

"Petri dishes really excel at growing bacteria and fungi," you say, reading on. "Heck, I could have told you that," Zack says, unimpressed. "Say, you writing all this down?"

Continue investigating the biology lab

An Access Excellence Science Mystery sponsored by Genentech, Inc.