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Homework Help: Disscusion for Bio Experiment

  1. Oct 18, 2005 #1
    im sorry i didnt know where to post this thread because it is homework but it isnt physics so i posted it here.

    I have a project in grade 12 biology that i have to write a disscusion on and i will give a quickl overveiw of the experiment because i need help on writing my disscusion.

    I have 0.5g of yeast mixed with 1.0g of 5 different sugars, Maltose, Dextrose, Fructose, Sucrose , Lactose, all mixed with 450ml of distilled water.The hole thig was an anarobic reaction so the yeast produced co2 and ethanol.
    the levels of co2 were measured and the only two that had a result were sucrose with 29ml of co2 produced and fructose with 22ml of co2 prduced.

    i have no more time to write anything else but i need help to write my disscusion, why the certain sugars did this. if you have any questions post them and i will answer them tonite.
  2. jcsd
  3. Oct 18, 2005 #2


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    This will probably get moved to the homework help section, but we can get you started here.

    Think about the two sugars that gave you a positive result, the sucrose and fructose. What do you know about them? What are their structures, how are they similar or diffferent to each other and also how are they similar or different from the other sugars that did not yield any CO2? Do you have any ideas as to why the yeast would only react with those two and not the others. How could you test those ideas? This should get you well into the discussion.
  4. Oct 20, 2005 #3
    thank you for the questions to write about even after a full day of research i have found no answers to any of these questions. So if any buddy on this site can help me in answering these quesitons it wopuld be greatly appretiated.
  5. Oct 20, 2005 #4


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    Tido, have you tried to look on PF for discussion about yeast and fermentation. We had a discussion in past about the type of sugar used by yeast under aerobic and anaerobic conditions.
  6. Oct 23, 2005 #5
    yes i have looked at the different threads for yeast fermentation and still nothing is close to what i am doin or what i am asking, and if it is i simply can't decode it.can some one tell me why my experiment went the way it did cause i have no clue
  7. Oct 23, 2005 #6


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    This thread has the answer why some sugar are utilize and other are not.

    For doctoxyn comment, look at the wikipedia pages and tell me what is the common thing between fructose and sucrose and that is absent in all the other sugar.

    For your all mixed sugar solution what was the concentration of each sugar?
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