If you're shooting a university's graduation, then odds are that most of the people in attendance are from out of town and plan to leave soon. In addition to the camera, tripod and flash, you should also have a great photo printer so that you can deliver the goods on the same day.
Polymerase chain reaction. Polymerase chain reaction, (PCR), a technique used to make numerous copies of a specific segment of DNA quickly and accurately.
The copying process, known as polymerase chain reaction (PCR), uses an enzyme (polymerase) to replicate DNA regions in a test tube. By repeating the copying process, a small number of DNA molecules can be reliably increased up to billions within several hours.