Why bacteria are difficult to see?
This is because:
1. The bacteria are small, typically 0.2-2 µm in diameter and 1-10 µm in their length.
2. Most bacteria are colorless under a standard light microscope, so it is hard to see.
What is a Gram stain?
The Gram stain was developed by the Danish bacteriologist Hans Christian Gram in 1884. It is one of the most useful and staining techniques in the Microbiology field. All bacteria can be classified into two large groups: gram-positive and gram-negative.
What are Gram stain steps?
1. Primary stain (crystal violet)
2. Mordant (iodine)
3. Decolorization (alcohol wash)
4. Counterstain (safranin)
Why do bacteria stain differently after Gram stain?
This is because gram-positive and gram-negative bacteria have different cell wall structures.