rich coat, the glycocalyx. The cell coat forms an integral part of the membranes of the smooth endoplasmic reticulum serve as surfaces for
plasma membrane, projecting as a diffusely filamentous layer 2–20 nm the attachment of many enzyme systems, e.g. the enzyme cytochrome
or more from the lipoprotein surface. The cell coat is composed of the P450, which is involved in important detoxification mechanisms and
carbohydrate portions of glycoproteins and glycolipids embedded in is thus accessible to its substrates, which are generally lipophilic. The
the plasma membrane (see Fig. 1.3). membranes also cooperate with the rough endoplasmic reticulum
The precise composition of the glycocalyx varies with cell type; many and the Golgi apparatus to synthesize new membranes; the protein,
tissue- and cell type-specific antigens are located in the coat, including carbohydrate and lipid components are added in different structural
the major histocompatibility complex of the immune system and, in compartments. The smooth endoplasmic reticulum in hepatocytes con-