One celled organisms are called unicellular organisms.
Organisms that are divided into classes are called classifying organisms or classified organisms.
Organisms that eat other organisms are called consumers or predators.
First an embryo (egg-stage), later a larva (freeswimming stage)
These organisms would be called mutants.
The process by which modern organisms have descended from ancient organisms is called evolution.
Organisms that hunt and kill other organisms for food are called predators.
Those organisms are called heterotrophic. These organisms either eat the autotrophs (organisms that make their own food) or eat the organisms that eat the autotrophs (also called the producers). Heterotrophs are also called "consumers."
Organisms that secure food by eating other organisms are called consumers. They obtain nutrients by consuming other living organisms.
Parasites.
These are called decomposers
they are also called unicellular organisms.