Endocytosis occurs when the cell membrane engulfs particles (dark blue) outside the cell, draws the contents in, and forms an intracellular vesicle called an endosome. This vesicle travels through ...

This takes place when molecules diffuse across the cell membrane by travelling through ... by the breakdown of ATP inside the cell. This diagram shows molecules moving from area of low ...

For example, the long, narrow muscle cell is ... is a nucleus -- a sphere-like structure separated from the rest of the cell by a membrane. The nucleus acts as the cell's control center ...

In this diagram of G-protein-coupled receptor activation ... These activated subunits can act on ion channels in the cell membrane, as well as cellular enzymes and second messenger molecules ...

A virus budding from a host cell membrane. This sequence of steps forms ... and how the virus is released from an organism (for example, through sneeze droplets or bodily fluids).

See COCHLEA for diagram. Incoming vibrations set up a travelling wave along the membrane giving it a different maximum displacement for different frequencies as shown below. The bulging of the ...

Human cells, for example, employ hundreds of different types ... which provides the basic structure for the cell membrane, and a non-bilayer-forming lipid, such as cholesterol, which adds ...