Answers to Review Questions List two types of microscopes that do not utilize stains for viewing cells. Darkfield and Phase Contrast microscopes. The gram stain is an example of a differential stain. True Mycobacteria are identified using a stain known as the acid-fast stain. India ink is used in negative staining to identify a bacterial cell's capsule.
Counterstains involve using a stain of a different color than the primary stain.