GOLGI COMPLEX
1. Golgi complex organelle was first discovered by an Italian neurologist Camillo Golgi (1898) in the Purkinje cells of the cerebellar cortex of the barn owl.
2. Golgi got Nobel Prize in 1906.
3. Golgi complex consists of flattened disc-like cisternae with dilated rims and associated vesicles and tubules.
4. Golgi complex is found in all eukaryotic cells except RBCs.
5. The first electron microscopic studies on the structure of Golgi complex have been done by Dalton and Felix (1954) in the epididymis of the rat.
6. Golgi complex consists of a series of flattened membrane vesicles or sacs.
7. Golgi vesicle has three well defined regions-the cis, the medial and the trans.
8. The transfer vesicle from RER fuse with cis region of Golgi complex where they deposit their proteins.
9. These proteins then progress from the cis to the medial and finally to the trans region.
10. The secretory vesicles leave the trans region and move towards plasma membrane.
11. Golgi complex of plants is usually called as dictyosome.
12. The term 'dictyosome' was coined by Perroncito (1910).
13. Dictyosome contains on the average 2-7 cisternae in stacked arrangement.
14. Cell organelles associated with secretion are Golgi bodies.
15. The Golgi complex functions primarily as a processing plant where proteins newly synthesized in endoplasmic reticulum are modified in specific ways.
Functions of Golgl Complex
• Secretion: The Golgi material is primarily associated with secretory activities of the cell.
• Storage: Dictyosomes serve as temporary storage place for proteins and other compounds synthesized by ER.
• Glycosylation: With the enzyme glycosyltransferase, characteristic of Golgi complex, proteins and lipids are glycosidated to form glycoproteins and glycolipids.
• Cell Wall Formation: Substance like pectins and hemi- cellulose are contributed by Golgi complex.
• Acrosome Formation: The acrosome present in the sper- matozoa is derived from Golgi bodies.
• Plasma Membrane Formation: Golgi complex plays an important role in the synthesis of carbohydrate component of plasma membrane.
• Lysosome Formation: The primary lysosomes are formed by Golgi complex.
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