BIOLOGY P32 DISCUSSION ONLY ( AS LEVEL )

[adkhan]

hey if u guys want u can take a look at this plan diagram ive attached, our teacher made us draw it today, the diagram is drawn neatly but please excuse my handwriting :S

Cheers, ADKhan

[musicfreak]

thank youu once again!!!
im gonna practise doing this den! 

[adkhan]

sorry mate thts how ive been told to do it, so i think im gonna stick to it, but can u actually elaborate on how u think it shud be done?
itll be much appreciated

[adkhan]

because as far as i have been told a PLAN DIAGRAM of a CELL consists of all of its layers and different cells wiothout their internal organelles, can u please tell me how it has been described to you?

[musicfreak]

well as what i know from what my teacher told me and shes an awsum teacher... a plan diagram shud only be lines...no cells shud b drawn...
so for like a plan diagram for the similar drawing u posted ..it wud luk summin like
_______________________________
_______________________________       the first small layer is for the upper epidermis
 
                                                         the 2nd layer after that for the palisade mesophyll
_______________________________      
                                                         the 3rd layer for spongy
                                                         4th for the lower epidermis...the width of the layer shud b that of similar ratio to the one in the
                                                         diagram... no cell drawing AND no shading..i lost mark in my mock for shading too... just outlines
                                                          if dey specify draw cells...den draw the cell but make no shading of nucleus etc..
_______________________________
_______________________________

[musicfreak]

yea k..ma badd... dint notice that... thanxx

[GreenGarden]

i don think from the point of veiw tat they actually neutralise..for me they act as inhibitor..think abt this ..if it function to neutralise.and we r using diff concentration of NaCl then the exp doesnt really show the activity of the yeast isn't it..

[adkhan]

to be honest i dint understand the plan diagram and the nacl portion either, but this teacher of mine is known to have leaked papers soooooo many times that i think itll be wise for me to just follow his instructions, i think tht the nacl will inhibit oo but wtevr

[musicfreak]

well it cud also mean the affect of ph on the enzyme and den testing the rate of rxn...like adding diff conc. of nacl to change the ph and keeping all oder variables like temp.. the conc of enzyme substrate etc... and den cheking the no of bubbles produced with each conc. of nacl..
im just guessing... i donno myself...
anyone else knows anything bout the p 32 bio and cud confirm??

[lys90]

but from what i read is nacl is one of the fermentory substrate/nutrients for yeasts. so either way is possible tho...but i have doubt on the pipette and syringe thingy..

[musicfreak]

well i think dey will tell us what the role of nacl is as we all donno..or if not we can guess it out when we r doing the expt... plus we actually dint measure the volume but counted the no of bubbles produced...

[lys90]

meaning the syringe thingy is just for measuring the amount of yeast we want?

[adkhan]

ahh, i called my tecacher found out the role of nacl, he gave me a link to this passage for bettr understanding

yeast fermentation is retarded in the presence of high concentrations of sugar and salt. This inhibitory effect is related to the high osmotic pressure gradient created outside of the yeast cells due to high concentrations of sugar and/or salt.

Salt also inhibits yeast activity if it is used at levels above 1% in the mixture.

[contagious]

is that about paper 31 or 32 if 32 may u plz give info about bio paper 31 plz

[GreenGarden]

yeast activity hav to be maintained at around 35 oC , so we need a water bath..well, i nvr try this kind of experiment b4 where we hav to prepare our own water bath.we normally use the machine kind ,already prepared .can any1 tell me how to do this ..heat the water once the temp reach around 35, takeaway bunsen burner then temp fall heat it again?i'm totally confused..