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.
Wedges. Wedges are a type of inclined plane. Instead of being stationary and having work done upon it, however, the wedge is an inclined plane that is moved through something else. As a wedge is forced into a space in an object, it exerts force to widen the space. An example of a wedge is an axe.Axes are used to split logs.As the axe is forced into a space in the wood, it pushes the two parts of the log apart. Many other types of cutting implements are also wedges, including knives, scissors, and teeth.s a wedge is forced into a space in an object, it exerts force to widen the space. An example of a wedge is an axe. Axes are used to split logs. As the axe is forced into a space in the wood, it pushes the two parts of the log apart.