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.
To wedge means to cut clay into manageable pieces and push and press on clay to expel all air bubbles trapped in the clay. If not done thoroughly, air bubbles will cause the clay piece to burst in the kiln, damaging the kiln and other pieces of work. Term.