While prokaryotic cells do not have membrane-bound structures, they do have distinct cellular regions (Figure 1). In prokaryotic cells, DNA bundles together in a region called the nucleoid. Primitive ...

Eukaryotes are organisms whose cells possess a nucleus enclosed within a cell membrane, making up one of the three domains of life, Eukaryota. They include multicellular organisms such as plants, ...

Prokaryotic cells have evolved numerous machineries to swim through liquid or crawl over surfaces. Perhaps the most common of these are the well-studied bacterial flagella and the unrelated archaeal ...

The chemical reactions on which life depends need a place to happen. That place is the cell. All the things which biology recognises as indisputably alive are either cells or conglomerations of cells ...