Preparation of smear & Simple Stains
Parts of a microscope
Bacteria are microorganisms. They are also colorless for the most part. In order to envision them to study their structure and shape , it becomes necessary to make them more easily visible.Simple stains use a single dye to color bacterial cells so that their size, shape and arrangement can be observed. Stains is general can be divided into three groups: Basic , Acidic and Neutral. A positively charged stain will stain a negatively charged structure much better (basic stain) , while a negatively charged dye will stain a positively charged structure better (acidic stain)
Simple staining : there are two methods: positive staining - where the actual cells are themselves colored and appear in a clear background; negative staining – where the cells remain clear (uncolored) and the background is colored .