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.

Coccobacilli are a type of bacteria that are shaped like very short rods or ovals. The name “coccobacilli” is a combination of the words “cocci” and “bacilli.” Cocci are sphere-shaped bacteria, while ...