The United Illuminating Company (UI) is a regional electric distribution company based in Orange, Connecticut.
Although generally not visible to the naked eye, organisms composed of prokaryotic cells still dominate the earth. Their collective mass is at least 10 times greater than the mass of all eukaryotes combined. Organisms composed of prokaryotic cells are classified into 2 main groups: archaea and bacteria. Archaea most closely resemble the first primitive cells on our planet.
3D animation of a prokaryotic cell that shows all the elements that compose it. A prokaryote is a single-celled organism that lacks a membrane-bound nucleus (karyon), mitochondria, or any other membrane-bound organelle. The word prokaryote comes from the Greek ÏÏÏ- (pro -) before and ÎºÎ±ÏÏÏÎ½ (karyon)  nut or kernel .nother difference is that ribosomes in prokaryotes are smaller than in eukaryotes. However, two organelles found in many eukaryotic cells, mitochondria and chloroplasts, contain ribosomes similar in size and makeup to those found in prokaryotes.