Most species of bacteria can be broadly divided into two groups, known as gram-positive and gram-negative. These categories ...

Gram positive vs gram negative Gram positive bacteria are surrounded by a single thick peptidoglycan cell wall and are therefore termed monoderms. Gram negative bacteria have a much thinner ...

Gram-negative bacteria show pink or red on staining and have thin walls. They release different toxins and affect the body in different ways. Gram-positive and Gram-negative are types of bacteria.

What do the results of a gram stain mean? If your gram stain results are negative, it means no bacteria were found in your sample. If they’re positive, it means bacteria were present.

Gram-positive bacteria have thick cell walls. A Gram stain test, which involves a chemical dye, stains the bacterium’s cell wall purple. On the other hand, gram-negative bacteria stain pink instead.

When bacteria retain the crystal violet dye during the Gram stain test, they are called Gram-positive bacteria. Learn more here.

Published by Hans Christian Gram in 1884, gram staining distinguishes gram-positive bacteria (purple) from gram-negative bacteria (pink). Gram-positive critters, such as staph, have a thick ...

Find out the differences between gram-positive bacillus and gram-negative bacillus and how they may affect health.