Microorganisms Harmful or Beneficial

Microorganism

A living thing that can only be seen with the aid of magnification. Microorganisms can be both helpful and harmful.

Producer

A living thing, like a green plant, that makes its food from simple substances and sunlight.

Protozoan

A single- celled animal-like organism that often lives in ponds and can produce their own food.

Decomposer

An organism, often a bacterium or fungus, that feeds on and breaks down dead plant or animal matter.

Organism

Any living thing. This includes humans, plants, insects, animals, and microorganisms.

Single-Celled Organism

Any organism that has only one cell. This is the smallest unit of life.

Bacteria

Microscopic single-celled organisms that exist everywhere and can make their own food.

Fungi

Organisms that are neither plant nor animals, but have characteristics of both and absorb food from whatever they are growing on.

Algae

Plant-like protists that live in water and contain chlorophyll. They produce oxygen and their own food.