A plasma membrane is permeable to specific molecules that a cell needs. Transport proteins in the cell membrane allow for selective passage of specific molecules from the external environment.

This is a passive process, which means it does not need energy. The oxygen diffuses across the partially permeable membrane of the alveoli cells and the capillary wall, into the red blood cells to ...

the authors demonstrate the possibilities of using 3D MINFLUX to track molecules inside living cells. This paves the way for future studies, for example, on passive nucleocytoplasmic transport ...