Microbiology Practice Exam

Gel electrophoresis is a laboratory technique that is effective in separating bacterial species based on their size and charge. This method involves applying an electric field to a gel matrix, causing charged molecules such as DNA or proteins to migrate through the gel. Since different bacterial species can have variations in their genetic material or protein profiles, gel electrophoresis facilitates the comparison and identification of these differences.

This technique is commonly used in molecular biology to analyze the genetic content of different bacteria or to assess the genetic diversity within a species through techniques such as DNA fragment analysis. The separation results in distinct bands that represent different bacterial species, aiding in their identification.

Other techniques mentioned have different primary purposes. Polymerase chain reaction (PCR) is primarily used for amplifying specific DNA sequences rather than separating species. Microscopy is useful for observing bacterial morphology but does not separate species based on their genetic or biochemical characteristics. Centrifugation primarily separates components based on density rather than molecular size or charge, which is less effective for distinguishing between different bacterial species.