URGENT HELP Pasteur's fermentaion experiment (1 Viewer)

[djet]

I'm doing a model of Pasteur's fermentation experiment in a couple of days but it is not the swan flask experiment. We are putting yeast into a test tube and sealing it with a cork (that has been applied with vaseline) to keep oxygen out and as to not let the CO2 accumulate inside the test tube. Then heating it up to ?? temp to kill the bacteria.

Does anyone have any further information for this experiment as i do not know the correct methods or aim or results table or the controlled variable..... (I think the control maybe not treating with heat??)

And i need help for the petri dish experiements which use agar. We will be picking an experiment out of a hat so don't know which one we'll be doing and need to know both!

 

[Survivor39]

Hi djet. Your description of both experiment is very brief and I am not sure how much help I can offer.

From what I can see, you are putting yeasts into some sort of starting material inside the flask and you are trying to observe if fermentation occurs in the presence of yeasts? (by the way, a yeast is not a bacterium. A yeast is a eukaryote and a type of fungi)

It makes sense because if you use heat to kill the yeast and sterlise the starting material, no fermentation would occur. If this what you need to do?

In the second experiment, you haven't given enough information for me to help you. I guess agar plate experment can be anything from exposing agar to air to see the presence of microbes in the air, finger-print the plate for microbes on skin surfaces etc. Obviously the correct control would be an unopened plate which should have no growth.

 

[djet]

All I know is we are simulating Pasteur's pasteurization experiment (modelling) and my teacher has given us half the information we need. My guess is that we need to show that heating a substance (not sure what it will be) will kill the bacteria while the yeast ferments ?? I have very little info on this and my classmates are all madly googling to find out. We're cool with the other experiment - have heaps of info - but half the class will be doing the experiment that we have no info on and theres nothing on the internet about it. think my teachers lost the plot. Its like 50% will have a great bio prac and 50% won't know what they're doing!

 

[Survivor39]

Both bacteria and yeast can ferment. There is no point killing one but not the other. Sorry I cannot help on this one.

 

[djet]

Thanks for trying to help on this one. Half the class had to do this fermenting exp we knew nothing bout and other half did an easy one on proving/disproving spontaneous generation using agar jelly on pp's. I got lucky - drew the pp experiment out of the luckydip box. Hope I can ask you q's again in the future if I get stuck with anything else - i've seen in this forum you've helped heaps of bio students over the years - thats really putting back.

 

[Rekkusu]

Ah nice, lucky you got the spontaneous generation. Should you need to write a report based upon this, I found it best to constantly relate to Koch's postulates as well.

If your teacher gives you extra marks based upon any extracurricular research you do, find something in which a certain bacteria was initially thought to be against Koch's postulates.