Lecture 16 - Chloroplast | Cell Biology- Botany PDF Download

 Page 1


Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
Lesson:  Chloroplast 
Lesson Developer: Rashmi Sharma 
College/ Department: Department of Botany, Acharya Narender Dev 
College, University of Delhi 
Page 2


Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
Lesson:  Chloroplast 
Lesson Developer: Rashmi Sharma 
College/ Department: Department of Botany, Acharya Narender Dev 
College, University of Delhi 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
1 
Table of contents 
 Lesson: Chloroplast 
? Introduction 
? Structure and function 
? Photosynthesis 
? Light dependent reactions 
? Electron transport 
? Synthesis of ATP 
? Non light dependent reactions 
? Marker Enzymes 
? Semi-autonomous nature 
? Sorting and import of proteins 
? Biogenesis 
 
? Summary  
? Exercises 
? Glossary 
? References  
 
 
 
 
 
 
 
 
 
Page 3


Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
Lesson:  Chloroplast 
Lesson Developer: Rashmi Sharma 
College/ Department: Department of Botany, Acharya Narender Dev 
College, University of Delhi 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
1 
Table of contents 
 Lesson: Chloroplast 
? Introduction 
? Structure and function 
? Photosynthesis 
? Light dependent reactions 
? Electron transport 
? Synthesis of ATP 
? Non light dependent reactions 
? Marker Enzymes 
? Semi-autonomous nature 
? Sorting and import of proteins 
? Biogenesis 
 
? Summary  
? Exercises 
? Glossary 
? References  
 
 
 
 
 
 
 
 
 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
2 
 
Introduction 
Chloroplasts are organelles involved in photosynthesis, the process of formation of 
carbohydrates from carbon-di-oxide and water in the presence of sunlight by the plants. 
 
 
Figure: Summarizing the photosynthetic reaction 
Source: http://www.hartnell.edu/tutorials/biology/images/photosynthesis_equation_pic.jpg 
 
 
Source:http://www.southtexascollege.edu/modeh/1408webpage_files/CH%207_files/image
005.jpg 
 
 
 
 
Page 4


Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
Lesson:  Chloroplast 
Lesson Developer: Rashmi Sharma 
College/ Department: Department of Botany, Acharya Narender Dev 
College, University of Delhi 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
1 
Table of contents 
 Lesson: Chloroplast 
? Introduction 
? Structure and function 
? Photosynthesis 
? Light dependent reactions 
? Electron transport 
? Synthesis of ATP 
? Non light dependent reactions 
? Marker Enzymes 
? Semi-autonomous nature 
? Sorting and import of proteins 
? Biogenesis 
 
? Summary  
? Exercises 
? Glossary 
? References  
 
 
 
 
 
 
 
 
 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
2 
 
Introduction 
Chloroplasts are organelles involved in photosynthesis, the process of formation of 
carbohydrates from carbon-di-oxide and water in the presence of sunlight by the plants. 
 
 
Figure: Summarizing the photosynthetic reaction 
Source: http://www.hartnell.edu/tutorials/biology/images/photosynthesis_equation_pic.jpg 
 
 
Source:http://www.southtexascollege.edu/modeh/1408webpage_files/CH%207_files/image
005.jpg 
 
 
 
 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
3 
 
 
 
 
 
 
 
 
 
 
 
Video: Structure and function of chloroplasts 
Source: http://www.britannica.com/EBchecked/topic/113761/chloroplast 
Chloroplasts were first described as ‘chloroplyllkornern’ (chlorophyll granules) by German 
botanist Hugo von Mohl in 1837, though because of their large size they were seen long 
back by Nehemiah Grew who described them in 1682 as green precipitates! It was A.F.W. 
Schimper who in 1883 introduced the term ‘plastids’ as a substitute for chlorophyll granule. 
In the same year A. Mayer described ‘grana’ as dense dot like structures embedded in the 
‘stroma’ of these plastids. The terms grana and stroma are still in use but chloroplast has 
replaced the term plastids for the green organelles of leaves. T.Engelmann a German 
biologist in 1881 identified the chloroplasts as the sites where photosynthesis occurs. He 
observed that outside the cells of green alga Spirogyra just close to the large ribbon shaped 
chloroplasts, bacteria would collect probably to utilize the oxygen being liberated during 
photosynthesis in the chloroplasts (bacterial chemotaxis).   
For details visit: http://link.springer.com/content/pdf/10.1007%2Fs11120-004-6313-8.pdf 
  
In addition to photosynthesis plastids are also involved in: 
? Synthesis of amino acids, fatty acids and lipid components of their membranes.  
? The important step of conversion of nitrite (NO
-
2
) to ammonia (NH
3
) occurs in the 
chloroplast providing the plant with the nitrogen for the synthesis of amino acids and 
nucleotides. 
A typical plant cell may have 20-40 chloroplasts. There are many alga which have single 
chloroplast per cell that occupies most of the cell (remember cup shaped chloroplast of 
Chlamydomonas). 
Page 5


Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
0 
 
 
 
 
 
 
 
 
 
 
 
 
Lesson:  Chloroplast 
Lesson Developer: Rashmi Sharma 
College/ Department: Department of Botany, Acharya Narender Dev 
College, University of Delhi 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
1 
Table of contents 
 Lesson: Chloroplast 
? Introduction 
? Structure and function 
? Photosynthesis 
? Light dependent reactions 
? Electron transport 
? Synthesis of ATP 
? Non light dependent reactions 
? Marker Enzymes 
? Semi-autonomous nature 
? Sorting and import of proteins 
? Biogenesis 
 
? Summary  
? Exercises 
? Glossary 
? References  
 
 
 
 
 
 
 
 
 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
2 
 
Introduction 
Chloroplasts are organelles involved in photosynthesis, the process of formation of 
carbohydrates from carbon-di-oxide and water in the presence of sunlight by the plants. 
 
 
Figure: Summarizing the photosynthetic reaction 
Source: http://www.hartnell.edu/tutorials/biology/images/photosynthesis_equation_pic.jpg 
 
 
Source:http://www.southtexascollege.edu/modeh/1408webpage_files/CH%207_files/image
005.jpg 
 
 
 
 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
3 
 
 
 
 
 
 
 
 
 
 
 
Video: Structure and function of chloroplasts 
Source: http://www.britannica.com/EBchecked/topic/113761/chloroplast 
Chloroplasts were first described as ‘chloroplyllkornern’ (chlorophyll granules) by German 
botanist Hugo von Mohl in 1837, though because of their large size they were seen long 
back by Nehemiah Grew who described them in 1682 as green precipitates! It was A.F.W. 
Schimper who in 1883 introduced the term ‘plastids’ as a substitute for chlorophyll granule. 
In the same year A. Mayer described ‘grana’ as dense dot like structures embedded in the 
‘stroma’ of these plastids. The terms grana and stroma are still in use but chloroplast has 
replaced the term plastids for the green organelles of leaves. T.Engelmann a German 
biologist in 1881 identified the chloroplasts as the sites where photosynthesis occurs. He 
observed that outside the cells of green alga Spirogyra just close to the large ribbon shaped 
chloroplasts, bacteria would collect probably to utilize the oxygen being liberated during 
photosynthesis in the chloroplasts (bacterial chemotaxis).   
For details visit: http://link.springer.com/content/pdf/10.1007%2Fs11120-004-6313-8.pdf 
  
In addition to photosynthesis plastids are also involved in: 
? Synthesis of amino acids, fatty acids and lipid components of their membranes.  
? The important step of conversion of nitrite (NO
-
2
) to ammonia (NH
3
) occurs in the 
chloroplast providing the plant with the nitrogen for the synthesis of amino acids and 
nucleotides. 
A typical plant cell may have 20-40 chloroplasts. There are many alga which have single 
chloroplast per cell that occupies most of the cell (remember cup shaped chloroplast of 
Chlamydomonas). 
Chloroplast 
Institute of Lifelong Learning, University of Delhi 
 
4 
Chloroplasts are organelles that belong to the plastid family. This group of organelles which 
are present in various plant cells differ in their color and function. In young meristems small 
pro-plastids develop which mature according to the requirement of the cell and also as 
dictated by the nuclear genome.  
 
Figure: A proplastid 
Source:http://www.skidmore.edu/academics/biology/plant_bio/photos/photos/cellbio/Propla
stid.jpg