the cell membrane is a lipid bilayer, but a cell has only one cell membrane. which organelles in this lesson have a double membrane?

The cell membrane is composed of two layers of phospholipids and is a fluid structure that's composed of four main molecules. DNA is transcribed into RNA within the nucleus and then RNA is transported to the cytoplasm. The lipid bilayer (or phospholipid bilayer) is a thin polar membrane made of two layers of lipid molecules. These membranes are flat sheets that form a continuous barrier around all cells. These membranes are flat sheets that form a continuous barrier around all cells.