Golgi bodies/Golgi Complex/Golgi Apparatus

Golgi complex or Golgi apparatus or Golgi body act as a assembly, manufacturing cum packaging & transport unit of cell.

i. Structure of Golgi complex:
a. Golgi complex consists of stacks of membranous sacs called cisternae.
b. Diameter of cisternae varies from 0.5 to 1μm.
c. A Golgi complex may have few to several cisternae depending on its function.
d. The thickness and molecular composition of
membranes at one end of the stack of a Golgi sac differ from those at the other end.
e. The Golgi sacs show specific orientation in the cell.
f. Each cisterna has a forming or 'cis' face (cis: on the same side) and maturing or 'trans' face (trans: the opposite side).
g. Transport vesicles that pinch off from transitional ER merge with cis face of Golgi cisterna and add its contents into the lumen.

ii. Location of Golgi complex:
Golgi bodies are usually located near endoplasmic reticulum.

iii. Functions of Golgi complex:
a. Golgi body carries out two types of functions, modification of secretions of ER and production of its own secretions.
b. Cisternae contain specific enzymes for specific functions.
c. Refining (modification) of product takes place in a sequential manner.
d. For example, certain sugar component is added or removed from glycolipids and glycoproteins that are brought from ER, thus forming a variety of products.
e. Golgi bodies also manufacture their own products. Golgi bodies in many plant cells produce non-cellulose polysaccharides like pectin.
f. Manufactured or modified, all products of Golgi complex leave cisternae from trans face as transport vesicles.

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