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 ...

A eukaryotic cell (left) has membrane-enclosed DNA, which forms a structure called the nucleus (located at center of the eukaryotic cell; note the purple DNA enclosed in the pink nucleus). A typical ...

All complex life forms on Earth, including plants and animals, are made up of eukaryotic cells; they are more sophisticated than bacterial or archaeal cells, which are prokaryotic. Eukaryotes have ...

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 ...