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Why is CO2 not produced in lactose Intolerance?

When Lactose reached the large intestine its broken down by microorganisms (fermentation).

The question is:
Q : Suggest a reason why the gas is unlikely to be CO2


Ive researched the internet and cant seem to find anything
I believe the microorganisms which use lactose as their respirative substrate break it down into a mixture of H2, CO2 and methane
Reply 2
Original post by jack97
When Lactose reached the large intestine its broken down by microorganisms (fermentation).

The question is:
Q : Suggest a reason why the gas is unlikely to be CO2


Ive researched the internet and cant seem to find anything


My best guess would be that it has something to do with the biochemistry in lactose metabolism by bacteria colonising in the colon. I remember something about hydrogen being the main gas product of lactose metabolism.
Reply 3
the question doesnt make sense to me, i always thought that CO2 was mainly produced in fermentation.

it may be because there are a similar amount of Carbons to Oxygens in its structure therefore there isnt enough oxygen to produce CO2. (12 CArbons and 11 Oxygens)
Reply 4
Hey, I'm not sure if this is the answer in the mark scheme/ model answer but read this:
http://www.uic.edu/classes/phar/phar332/Clinical_Cases/carbo%20metab%20cases/lactose%20intol.htm
Apparently, bacteria use co2 and hydrogen to produce methane and this causes the concentration of CO2 to decrease.
Hope this helped
Reply 5
Carbon dioxide is formed in aerobic respiration, whereas conditions in the colon are anaerobic.

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