Many viruses, including that perennial winter affliction, the influenza virus, are protected by a lipid membrane on loan from the host cell. The fusion proteins on the surface of the membrane are ...

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 ...

Prokaryotic cells, which include all bacteria and archaea, are ancient, and relatively simple compared to eukaryotic cells, which are found in fungi, plants, and animals. Scientists have long sought ...

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 ...

Prokaryotes are organisms whose cells lack a nucleus and other organelles. Prokaryotes are divided into two distinct groups: the bacteria and the archaea, which scientists believe have unique ...

Eukaryotes—fungi, plants, us—are complex. Our large cells are characterized by their different compartments, many of which are neatly enclosed within a boundary of membrane. These compartments contain ...

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 ...