Brownsville is a borough in Fayette County, Pennsylvania, United States, officially founded in 1785 located 35 miles (56 km) south of Pittsburgh along the Monongahela River.
2nd Item Specification: Given a group of organisms and a key, classify organisms based on observable characteristics. Depth of Knowledge Level 1. 1  A tool used by scientists to identify unknown organisms based on observable characteristics is called a. 2  dichotomous key.
Indicator organisms are organisms used as a sign of quality or hygienic status in food, Dietary supplements, water, or the environment. The initial goal in finding a safety indicator was to find a group of bacteria that could indicate the presence of fecal material and serve as a surrogate for Salmonella, but was easier and simpler to detect.