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Golgi Apparatus

Golgi Apparatus
Introduction
Golgi apparatus is also known as Golgi bodies or Golgi complex. In plants, these are also called as ‘Dictyosomes’
Discovery
Golgi apparatus was discovered by Golgi in 1898.
Production
These are produced by budding of SER and are gathered around cisternae.
Structure
Golgi complex is formed by cisternae alongwith associated vesicles.
  • Cisternae are stacks of flattened, membrane-bounded sacs.
  • Associated vesicles are complex system of interconnected tubules around the central stacks.
  • The whole stack consists of a number of cisternae.
  • Their outer convex surface is the forming face, while the inner concave surface is the maturing face. Vesicles are separated from cisternae from maturing face.
Functions
(i) Cell Secretions
Golgi complex is concerned with cell secretions. Mechanism of formation of these products is as; Formation of products on ribosomes, transport to Golgi apparatus for conversion into finished products, packing of finished products, export to outside through Golgi bodies or endoplasmic reticulum. For example in mammals, the pancreas secretes granules containing enzymes that help in digestion. The Golgi complex has a role information of these granules.
This fignre shows relationship of endoplasmic reticulum 
with Golgi Apparatus, lysosomes and plasma membrane.
(ii) Transport outside the Cell
The proteins or enzymes, which have to be transported out of the cell, pass through the Golgi apparatus.
(iii) Modification in Molecules
The most important function is to modify the proteins and lipids by adding carbohydrates and converting them into glycoproteins and glycolipids.

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