Prokaryotes have only one lipid bilayer- the cell membrane (also known as the plasma membrane). Many prokaryotes also have a cell wall, but the cell wall is composed of proteins or long chain carbohydrates, not lipids.
3. countable noun. A wedge is an object with one pointed edge and one thick edge, which you put under a door to keep it firmly in position. 4. countable noun. A wedge is a piece of metal with a pointed edge which is used for splitting a material such as stone or wood, by being hammered into a crack in the material.
I made a big fat wedge from that job. The wedge is used in Czech and is illustrated by the Czech name for the diacritic, haÄek. The tilde and the circumflex have a place in the ASCII scheme but the wedge and the umlaut do not. The hÃ¡Äek or âwedgeâ <Ë> is a diacritic commonly used in Slavic orthographies. [â¦] As a tone mark the wedge is used iconically for a falling-rising tone as in Chinese Pinyin. (phonetics) The IPA character <Ê>, which denotes an open-mid back unrounded vowel.