Prokaryotic organisms fall into two domains: bacteria and archaea, which contain autotrophs and heterotrophs. Regardless of domain, prokaryotes share common traits of being single-celled organisms that are the smallest a... More »

Bacteria are some of the best examples of prokaryotic organisms. These organisms do not have a membrane-bound nucleus and lack the well-distinguished cell features found in eukaryotes. More »

Prokaryotic organisms belong to the kingdom Monera, which contains bacteria. The main classes of bacteria are eubacteria and archaebacteria. These prokaryotic organisms are unicellular and can live in different environme... More »

Autotrophs and heterotrophs differ in the way they obtain energy; autotrophs make their own energy whereas heterotrophs must consume other organisms to get their energy. Autotrophs are the producers of ecosystems, which ... More »

The two domains of prokaryotes, which are archae and bacteria, contain the common organisms of cyanobacteria, halophiles and hyperthermophiles. Prokaryotes occur in many forms, and some species are more common than other... More »

The five main groups of single-celled organisms are protozoa, archaea, bacteria, unicellular fungi and unicellular algae. While single-celled organisms can be either eukaryotic or prokaryotic, most are prokaryotes. The t... More »

Both bacteria and archaea are organisms consisting of a single cell that lacks a nucleus or organelles. Even though these two groups are evolutionarily unique, there are a number of similarities. It is easy to see why ar... More »