The relationship lead to the permanent association and integration leading to eventual evolution of eukaryotes.
Membranes that may be double or single layered line cell organelles. The Mitochondria, chloroplast and the nucleus (not strictly an organelle) have double layered membranes, while the Lysosomes, Golgi apparati, vacuoles and so on have a single membrane. The Ribosomes are non-membranous structures.
The structural representation in the fluid mosaic model of the plasma membrane is universal in all living cells (plants & animals) and consists of two layers of phospholipids (lipids attached to a phosphate unit, proteins that dynamically move about the membrane and a small amount of glycoproteins (glucose bonded to proteins).
The lipid molecules are "amphiphilic," having a hydrophilic (water loving) portion facing outside and a hydrophobic (water shunning) lipid portion turned inside. (Campbells' Biology Chapter 8; Dalton.M Chapter2/membrane/html.)
Primarily, there are10 different types of lipids reported in cell membranes with different types of cells/organelles having differing percentage of each lipid, protein, and carbohydrate. ...