Answer:
Bacteria
Explanation:
Bacterial are prokarotes, that inhabit virtually all habitats..Although some may be pathogenic, ,most bacteria are beneficial. They live in mutual relationship with their living hosts.where they help most in catabolic reactions especially in digestion of food and in nutrient cycle.
They lack membrane bound organelles,they have cell wall made up of peptidoglycan, their nucleus is not bounded with double membrane like Eukaryotes.They vary in shapes, most are spherical in shape, with the shape determined by the cell wall and the cytoskeleton in the cystosol.
