Students conduct a Gram stain analysis of a bacterial culture to support a diagnosis and antibiotic treatment. When the slide is visualized under the microscope, students use the control smears to diagnose how decolorization went. They sort out challenges with Gram staining, including mistakes with decolorization, use of an aging culture, and interpretation of control smears.

Students use aseptic technique to transfer a bacterial culture to various media without contamination. They work progressively through the steps of aseptic technique using three culture media. While transferring from the first media, student errors are identified and corrected. During the second transfer, students have to rely on what they learned previously to make decisions, but their errors are caught and corrected. In the final transfer, they must recall the steps of aseptic technique and apply them.