Bacterium 〈99% SAFE〉

Common forms include cocci (spherical), bacilli (rod-shaped), and spirilla (spiral).

Scientists use a Gram stain to classify them. Gram-positive bacteria have a thick peptidoglycan layer that retains purple dye, while Gram-negative bacteria have a thinner layer and an outer membrane, appearing pink. bacterium

Bacteria play a critical role in maintaining the planet's balance: Common forms include cocci (spherical)

Engineered bacteria produce insulin, vaccines, and enzymes used in detergents. 4. Human Health and the Microbiome bacterium

Bacteria are generally categorized by their shape and the composition of their cell walls: