Search also in: Web News Encyclopedia Images. striking 1 adj Something that is striking is very noticeable or unusual. The most striking feature of those statistics is the high proportion of suicides..., He bears a striking resemblance to Lenin. â¦ strikingly adv usu ADV adj In one respect, however, the men really were strikingly similar., ...a strikingly handsome man... 2 adj Someone who is striking is very attractive, in a noticeable way. She was a striking woman with long blonde hair.
cell membrane. the outer boundary of the cytoplasm, a layer that controls what enters and leaves a cell.thin, flexible barrier around a cell, regulates what enters and leaves the cell. cell wall. a protective outer covering that lies just outside the cell membrane of plant cells.
All cells have an outer plasma membrane that regulates not only what enters the cell, but also how much of any given substance comes in. Unlike prokaryotes, eukaryotic cells also possess internal membranes that encase their organelles and control the exchange of essential cell components. Both types of membranes have a specialized structure that facilitates their gatekeeping function.