An organism is a living thing. This parrot is an organism.
Population-
A population is a group of similar organisms that share the same area. This is a picture of a group of parrots sharing the same space.
Community-
A community is made up of a bunch of different populations that live in the same area. These are some different animals that live in the rainforest together.
Ecosystem-
An ecosystem is a community together with its nonliving environment. This is a picture of an ecosystem with many different organisms,communities, and non-living things... such as water,and air. Some of the living things in the picture are: