Differential stains work by using a series of dyes, and sometimes additional chemicals, to stain bacteria contrasting colors based on structural difference between bacterial cells. The Gram stain, acid-fast stain and endospore stain each reveal distinct information about the bacteria tested.
What the Gram Stain Reveals about Bacteria
The Gram stain, developed by Christian Gram in the 1800’s, was the first differential staining technique in use and is still an important tool for distinguishing between two main types of bacteria—Gram-positive and Gram-negative.
Nearly all bacteria have a cell wall containing peptidoglycan, a molecule unique to bacteria. Gram-positive bacteria have a cell wall composed almost entirely of peptidoglycan, present in many layers. Gram-negative bacteria have a cell wall with only a thin layer of peptidoglycan beneath an outer cell wall membranous layer composed of lipopolysaccharides (LPS), an endotoxin that can be harmful to organisms infected with Gram-negative bacteria.
- For Aerobic Exercise
Learn about how to do a knees up high and low impact aerobic exercise from a fitness expert in this free exercise video on high and low impact aerobics ...
- Upflow Anaerobic Sludge Blankets
- Aerobic System Wastewater
- Aerobic Water Exercises
- Aerobic Workout At Home