bacteria are classified as prokaryotes, which are unicellular life forms.
Gram-negative bacteria have an outside lipid membrane layer growing surrounding the cell membrane and a thin peptidoglycan layer, whereas Gram-positive bacteria have a thick peptidoglycan layer and no outer lipid membrane.
They stain purple-blue because gram-positive bacteria have a lot of peptidoglycan in their cell walls, which helps them hold onto crystal violet dye. Gram-negative bacteria color red-pink because their cell walls contain less peptidoglycan and can't bind crystal violet dye.
Learn more about gram-positive bacteria here brainly.com/question/12292625
#SPJ4.
