Explain why the following conditions are necessary for photosynthesis.

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  a)  Carbon  (IV)  Oxide Required  in  the  dark  stage  of  photosynthesis;  it  combines  with  the  hydrogen  ion  from  the  light stage;  to  form  glucose,  proteins  and  lipids;  low  concentrations  reduces  the  rate  of  production  of energy  and  food;  while  high  concentrations  leads  to  an  increase  in  the  amount  of  energy  and food  formed; b)  Light It  is  used  to  break  down  water  molecules  (through  photolysis);  into  hydrogen  ions,  oxygen  and energy;  the  energy  and  hydrogen  ions  formed  are  used  in  the  dark  stage; c)  Chlorophyll Green  pigment  that  traps  light  energy  from  the  sun;  that  is  used  in  photolysis  of  water molecules; d)  Suitable  temperature  and  pH Temperature  affects  the  enzymes  involved  in  photosynthesis;  suitable/optimum  temperatures activate  enzymes;  for  maximum  production  of  food;  while  extremely  low  temperatures inactivate  enzymes;  leading  to  less  or  no  production  of  food;  high  temperatures  denature enzymes;  stopping  the  process  of  photosynthesis;  photosynthetic  enzymes  work  well  in  low  pH; so  the  rate  is  high;  while  higher  pH  reduces  enzyme  activity;  lowering  the  rate  of photosynthesis;   e)  Water   Forms  a  medium  for  the  chemical  reactions;  it  is  split  to  yield  hydrogen  ions,  oxygen  and  energy for  use  in  the  dark  stage;  solvent  for  the  materials  used  in  photosynthesis;  Max.  20  mks 

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