effect of temperature on the survival of yeast cells

[CrimsonFalcon]

im struggling a little on writing the theory... what should i be putting into it? i can gues roughly but im still not so sure. anyone that can help here?

[Steen]

i didn't realise they could even talk

THey cant - to YOU. Im sure its nothing personal

Test tube breakeage - good idea - especially if using a water bath to heat - wet test tubes + clumsy people (me) = disaster

[CrimsonFalcon]

thanks ^_^ well, you gotta think of everything. but im still stuck on the theory bit.... as well as i still have no idea of what the temp yeasyt denatures at. my preliminaries failed so much that im not even going to include them. everything else i have in the bag ^_~

[Steen]

My prelims suggested between 60 and 70. But some websites are quoting mid-40's but this may give you a rough guide. It's probably worth thinking about why your prelims failed in order to cover this for the actual plan - then you can include them anyway. And Im not sure what you mean by the theory so I cant comment there.

[SKG]

hi, i'm doing this plan thing too. how much of the yeast do we put in and how much sugar solution do we put in? someone told me 1 part yeast and 5 parts glucose but then another person told me it's the other way round! and also, i tried a preliminary one and my mixture just kept going a lighter blue - it didn't go clear, even at like 70oC !!please help! thanx

[CrimsonFalcon]

ah okies. i heard between 60-70, so i think ill go with that one, seems safest i guess. im not too sure how the experiments i did went wrong, but ill sort that i gues..

your meant to back up your work with some theory stuff apparently, liek umm abit about the stuff your using or something? im not too sure which is why im asking :/

[CrimsonFalcon]

someone told me 1 part yeast and 5 parts glucose but then another person told me it's the other way round! and also, i tried a preliminary one and my mixture just kept going a lighter blue - it didn't go clear, even at like 70oC !!please help! thanx

mine didnt work either, but if you read back in this forum there are a few people who have posted soem useful info on how to do it.

i think 1:1 would be okay, but i have nothing to back that up with. i supose it wouldnt be 5 yeast to 1 sugar as the yeast will be in competition for it then they wont get any to react with.

[Steen]

My first set of prelims didnt work cos the methylene blue was too dark for the amounts of yeast and glucose I was using - so It wasnt being turned colourless so I used more (glucose and yeast) in effect making the methylene blue more dilute.

Mine took quite a while to go colourless - however if they were kept warm (the same temperature as the yeast was) it went faster I found

[CrimsonFalcon]

i simply did mine wrong. i kinda followed a method from here, and that didnt work. the thermostat kept on getting changed by others occasionally, then there was the fact i put it right into the temp when you are meant to ease the heat on. sooo..

for my plan ive said i will empty the water bath and reheat the water to 30-40 degrees, put in the test tube of mixture stuff, then heat it up gradually therefore it wont denature the yeast.
then i guess you leave it for 10 mins at the desired temperature and go from there.

[CrimsonFalcon]

remember, this is only like what? 4 or 8 % of our total grade? so dont fret if you mess it up. 16 marks isnt going to kill you, and if you get the Aim, hypothesis and plan down at least that is going to give you some marks *grins*

[CrimsonFalcon]

Oh yeah!! also say to wash yah hands.... cause like, the methylene could be poisonnous?? i have no idea, best check that out but its a valid point too.

[funky pisces]

HEY....
DOES ANY1 KNOW WHIVH SECTION WE SHOULD INCLUDE OUR LIST OF VARIABLES THAT WE ARE CONTROLLNG? LIKE SHOULD WE PUT IT IN DA METHOD OR DA PREDICTION OR HAV A SEPERATE SECTION?

FKNX
FUNKY PISCES