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

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

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.

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.

Learn the differences between gram positive vs gram negative bacteria, including structure, stain results and examples of key bacterial species.

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

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 ...