Into tube 1, place 1 ml of your onion DNA solution. Into tube 2, place 1 ml of the standard DNA solution (this is a positive control). Make a negative control with the third tube by placing 1 ml of distilled water into it.WARNING: The Diphenylamine reagent is very acidic.he only difference is in what the DNA codes for, onions on one hand and humans on the other. The first step in extraction of any chemical from cells is the disruption of cells so that the chemical is released. To do this with onion DNA, two techniques are used in this laboratory.
A person with a perforated bowel has a hole in the wall of the stomach, small intestine, or large intestine. The perforated bowel allows food or stool to leak into the abdomen.
Vibrio cholerae is carried in the cholera victim's feces, urine, and vomitus, and is transmitted to others in contaminated water or food. Once it has reached the intestines, the intestinal lining becomes inflamed and the passages distended with a thin, watery fluid.ransmission. Vibrio cholerae is carried in the cholera victim's feces, urine, and vomitus, and is transmitted to others in contaminated water or food. Once it has reached the intestines, the intestinal lining becomes inflamed and the passages distended with a thin, watery fluid. Symptoms.