Content
     
         Learning Outcomes
     
         Autotrophic organisms
     
         Heterotrophs
     
         Photosynthesis
     
         Light absorption by the chloroplast              
     
         The stages of photosynthesis
     
         The C4 plants
     
         Factors affecting photosynthesis
     
        The measurement of photosynthesis
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                      Learning Outcomes
    After studying this session, you should be able to
     
    
       explain the mode of obtaining their energy requirement   
        for maintenance of their biological activities.
    
       describe the structure of leaf, chloroplast and different 
         pigments  associated with photosynthesis
    
       describe the  portions of photosynthetically active areas  
         in the electromagnetic spectrum 
    
       explain that light energy is converted to chemical energy,  
        and carbon is fixed into organic compounds.
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   
      describe how light is captured by the plants by means of 
       pigments and the structural adaptation to do so.
   
      distinguish between the two processes involved in the 
       photosynthesis i.e., Phase I and Phase II.
   
      explain photophosphorylation, the process in which 
       NADPH and ATP are generated.
   
      briefly describe the Calvin cycle and its important   
       reactions. Distinguish between the C3 and C4 pathways of 
     
       photosynthesis. 
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       How do we get energy to do our work?
       
           From food of course.
         Can we synthesize our food within 
                           our bodies?
       
           No we cannot.  So we are referred to as 
           “heterotrophs”. But there are organisms having the 
           ability to synthesize their own food within their     
           bodies.They are called “autotrophs”.
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        Categorization of organisms depending   
                 
                         on their food habits
                                                     Organisms
                                                     Organisms
                              Autotrophic                                  Heterotrophic
                              Autotrophic                                  Heterotrophic
                  Phototropic             Chemotropic
                  Phototropic             Chemotropic             Parasitic         Saprophytic
                                                                  Parasitic         Saprophytic
     Use energy of sun light      Use energy of a chemical     Live within another         Obtain food from 
     for the synthesis of food     reaction for the synthesis  organism and obtain         decaying matters 
     Eg. All green plants,        of food                      nutrition from the host
     Cyanobacteria                Eg. Some bacteria like 
     And some bacteria            Ferrous bacteria
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