Lecture 7 - Golgi Apparatus | Cell Biology- Botany PDF Download

 Page 1


Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 
 
 
 
 
 
 
 
 
 
 
Lesson: Golgi Apparatus 
Lesson Developer: Rina Majumdar 
College/Department: Maitreyi College, University of Delhi 
Page 2


Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 
 
 
 
 
 
 
 
 
 
 
Lesson: Golgi Apparatus 
Lesson Developer: Rina Majumdar 
College/Department: Maitreyi College, University of Delhi 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 1 
 
Table of Contents       
 
Chapter: Golgi apparatus                                                            
? Introduction  
? Structural organization of the Golgi Complex 
? Functions performed by the Golgi Complex 
? Role in Secretion 
? Protein processing 
? Proliferation of plasma membrane 
? Metabolism of lipids and polysaccharide 
? Sorting and Export of protein  
? Role of Coat Proteins in cargo selection and 
vesicle budding 
? Vesicle fusion 
? Plant cell wall formation 
? Acrosome development in animals 
? Summary  
? Exercise/ Practice 
? Glossary 
? References/ Bibliography/ Further Reading 
 
Page 3


Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 
 
 
 
 
 
 
 
 
 
 
Lesson: Golgi Apparatus 
Lesson Developer: Rina Majumdar 
College/Department: Maitreyi College, University of Delhi 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 1 
 
Table of Contents       
 
Chapter: Golgi apparatus                                                            
? Introduction  
? Structural organization of the Golgi Complex 
? Functions performed by the Golgi Complex 
? Role in Secretion 
? Protein processing 
? Proliferation of plasma membrane 
? Metabolism of lipids and polysaccharide 
? Sorting and Export of protein  
? Role of Coat Proteins in cargo selection and 
vesicle budding 
? Vesicle fusion 
? Plant cell wall formation 
? Acrosome development in animals 
? Summary  
? Exercise/ Practice 
? Glossary 
? References/ Bibliography/ Further Reading 
 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 2 
Introduction 
One of the important components of the endomembrane system is the organelle- Golgi 
apparatus (also called Golgi complex) that is principally involved in modifications and exocytic 
(the outside of the cell) protein trafficking. The Golgi apparatus is organized into stacks of 
usually four to six (as may as 60 in unicellular flagellates) flattened membrane bound 
compartments called cisternae that are stacked one over the other.  
 
Figure : Electron micrograph and a diagrammatic representation of Golgi apparatus 
Source: 
http://php.med.unsw.edu.au/cellbiology/images/thumb/4/41/Golgi_apparatus_EM_and_cartoo
n.jpg/391px-Golgi_apparatus_EM_and_cartoon.jpg 
Page 4


Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 
 
 
 
 
 
 
 
 
 
 
Lesson: Golgi Apparatus 
Lesson Developer: Rina Majumdar 
College/Department: Maitreyi College, University of Delhi 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 1 
 
Table of Contents       
 
Chapter: Golgi apparatus                                                            
? Introduction  
? Structural organization of the Golgi Complex 
? Functions performed by the Golgi Complex 
? Role in Secretion 
? Protein processing 
? Proliferation of plasma membrane 
? Metabolism of lipids and polysaccharide 
? Sorting and Export of protein  
? Role of Coat Proteins in cargo selection and 
vesicle budding 
? Vesicle fusion 
? Plant cell wall formation 
? Acrosome development in animals 
? Summary  
? Exercise/ Practice 
? Glossary 
? References/ Bibliography/ Further Reading 
 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 2 
Introduction 
One of the important components of the endomembrane system is the organelle- Golgi 
apparatus (also called Golgi complex) that is principally involved in modifications and exocytic 
(the outside of the cell) protein trafficking. The Golgi apparatus is organized into stacks of 
usually four to six (as may as 60 in unicellular flagellates) flattened membrane bound 
compartments called cisternae that are stacked one over the other.  
 
Figure : Electron micrograph and a diagrammatic representation of Golgi apparatus 
Source: 
http://php.med.unsw.edu.au/cellbiology/images/thumb/4/41/Golgi_apparatus_EM_and_cartoo
n.jpg/391px-Golgi_apparatus_EM_and_cartoon.jpg 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 3 
 The Golgi apparatus (also called Golgi complex) was named after its discoverer, Camillio Golgi 
(an Italian biologist), who for the first time described the structure in 1898 
(http://www.nobelprize.org/nobel_prizes/medicine/laureates/1906/golgi-bio.html). 
 
Figure: Camilio Golgi 
Source: http://upload.wikimedia.org/wikipedia/commons/6/69/Camillo_Golgi,_1889.JPG 
Golgi complex generally functions as the “Director” of the cell since it has very little role in 
synthesis, rather it is involved primarily in the biochemical modification and sorting of the 
materials already synthesized within the ER, to their specific destinations within the cell, to 
maintain cellular integrity of an active cell.  The three major destinations of the processed 
proteins and lipids from the Golgi, already synthesized in the lumen of the ER are the 
lysosomes, plasma membrane and extra cellular secretion.  The close interrelationship among 
the three cellular organelles namely ER, Golgi and Lysosome is referred to as GERL Complex.   
 
 
 
 
 
 
Page 5


Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 
 
 
 
 
 
 
 
 
 
 
Lesson: Golgi Apparatus 
Lesson Developer: Rina Majumdar 
College/Department: Maitreyi College, University of Delhi 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 1 
 
Table of Contents       
 
Chapter: Golgi apparatus                                                            
? Introduction  
? Structural organization of the Golgi Complex 
? Functions performed by the Golgi Complex 
? Role in Secretion 
? Protein processing 
? Proliferation of plasma membrane 
? Metabolism of lipids and polysaccharide 
? Sorting and Export of protein  
? Role of Coat Proteins in cargo selection and 
vesicle budding 
? Vesicle fusion 
? Plant cell wall formation 
? Acrosome development in animals 
? Summary  
? Exercise/ Practice 
? Glossary 
? References/ Bibliography/ Further Reading 
 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 2 
Introduction 
One of the important components of the endomembrane system is the organelle- Golgi 
apparatus (also called Golgi complex) that is principally involved in modifications and exocytic 
(the outside of the cell) protein trafficking. The Golgi apparatus is organized into stacks of 
usually four to six (as may as 60 in unicellular flagellates) flattened membrane bound 
compartments called cisternae that are stacked one over the other.  
 
Figure : Electron micrograph and a diagrammatic representation of Golgi apparatus 
Source: 
http://php.med.unsw.edu.au/cellbiology/images/thumb/4/41/Golgi_apparatus_EM_and_cartoo
n.jpg/391px-Golgi_apparatus_EM_and_cartoon.jpg 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 3 
 The Golgi apparatus (also called Golgi complex) was named after its discoverer, Camillio Golgi 
(an Italian biologist), who for the first time described the structure in 1898 
(http://www.nobelprize.org/nobel_prizes/medicine/laureates/1906/golgi-bio.html). 
 
Figure: Camilio Golgi 
Source: http://upload.wikimedia.org/wikipedia/commons/6/69/Camillo_Golgi,_1889.JPG 
Golgi complex generally functions as the “Director” of the cell since it has very little role in 
synthesis, rather it is involved primarily in the biochemical modification and sorting of the 
materials already synthesized within the ER, to their specific destinations within the cell, to 
maintain cellular integrity of an active cell.  The three major destinations of the processed 
proteins and lipids from the Golgi, already synthesized in the lumen of the ER are the 
lysosomes, plasma membrane and extra cellular secretion.  The close interrelationship among 
the three cellular organelles namely ER, Golgi and Lysosome is referred to as GERL Complex.   
 
 
 
 
 
 
Golgi Apparatus 
Institute of Lifelong Learning, University of Delhi 4 
Embed Animation :Inside of the cell 
Source: http://publications.nigms.nih.gov/insidethecell/extras/tomogram.mov 
Embed Animation: The transport of proteins through the endomembrane system. 
Source: http://bcs.whfreeman.com/thelifewire/content/chp04/0402002.html 
 
Figure : Endomembrane system 
Source: http://commons.wikimedia.org/wiki/File:Endomembrane_system_diagram_en.svg 
 Structural organization of the Golgi Complex 
(a)  The structure of the Golgi differ in different types of tissues, also varies with the metabolic 
status of the cell. 
(b) Golgi complex is characterised by a series of oval, flattened membrane bound discs with 
enlarged ends called the cisternae, arranged in stacks. 
(c)  The series of cisternae, each having a diameter of 500-1000 nm, is called a Golgi Stack 
in animal cells and dictyosomes (means stack like) in plant cells. 
(d)  The number of cisternae per Golgi stack varies from 4-8, though in secretory cells there 
may be 100-1000 Golgi stacks.  
(e) The cisternae margins of each Golgi stacks, are slightly curved to give the Golgi complex a 
bow-like appearance.