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.
A gap wedge's angle varies between 50 and 54 degrees. The pitching wedge is usually around 45 degrees while the sand wedge is between 54 and 58 degrees. Golf club makers have decreased pitching wedge loft degrees over recent years, with the gap wedge becoming an option for golfers.