synthesised in SER. . . .
Golgi apparatus Golgi apparatus Golgi apparatus Golgi apparatus Golgi apparatus Camillo Golgi ( ) first observed densely stained reticular structures near the nucleus. These were later named Golgi bodies after him. They consist of many flat, disc-shaped sacs or cisternae of . µ m to .
µ m diameter (Figure . ). These are stacked parallel to each other. Varied number of cisternae are present in a Golgi complex.
The Golgi cisternae are concentrically arranged near the nucleus with distinct convex cis or the forming Figure . Endoplasmic reticulum Cisternae Figure . Golgi apparatus face and concave trans or the maturing face. The cis and the trans faces of the organelle are entirely different, but interconnected.
The golgi apparatus principally performs the function of packaging materials, to be delivered either to the intra-cellular targets or secreted outside the cell. Materials to be packaged in the form of vesicles from the ER fuse with the cis face of the golgi apparatus and move towards the maturing face. This explains, why the golgi apparatus remains in close association with the endoplasmic reticulum. A number of proteins synthesised by ribosomes on the endoplasmic reticulum are modified in the cisternae of the golgi apparatus before they are released from its trans face.
Golgi apparatus is the important site of formation of glycoproteins and glycolipids. . . .
Lysosomes Lysosomes Lysosomes Lysosomes Lysosomes These are membrane bound vesicular structures formed by the process of packaging in the golgi apparatus. The isolated lysosomal vesicles have been found to be very rich in almost all types of hydrolytic enzymes (hydrolases – lipases, proteases, carbohydrases) optimally active at the acidic pH. These enzymes are capable of digesting carbohydrates, proteins, lipids and nucleic acids. .
. . Vacuoles Vacuoles Vacuoles Vacuoles Vacuoles The vacuole is the membrane-bound space found in the cytoplasm. It contains water, sap, excretory product and other materials not useful for the cell.
The vacuole is bound by a single membrane called tonoplast. In plant cells the vacuoles can occupy up to per cent