Why is it essential to apply heat during endospore staining?
Applying heat during endospore staining helps in the penetration of the primary stain, usually malachite green, into the endospore wall. Heat acts as a mordant that allows the stain to bind more effectively to the endospore, enhancing its visibility under the microscope. This technique improves the contrast between the endospore and the rest of the cell, aiding in their identification and study.