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rae
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#21
Report 16 years ago
#21
(Original post by Wilsoncswai)
so are you saying that the propanone is used to kill the seeds in tomato? why kill the seeds? coz i believe propanone is an inhibitor itself- i.e. it wouldnt allow cress seeds to germinate in propanone. are you doing the dry mass? measuring dry mass ? if yes how do you do it?
no, propanone will kill the cress seeds
no, not doing dry mass. seeing % germination after 2 days
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Wilsoncswai
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#22
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#22
do you use propanone to kill the cress seeds first before extracting getmination inhibitors?
how do you find out % of germination?
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rae
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#23
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#23
(Original post by Wilsoncswai)
do you use propanone to kill the cress seeds first before extracting getmination inhibitors?
how do you find out % of germination?
i think youre missing the point a bit. the inhibitors come from the tomato. you apply this, in water or propanone, to the cress seeds. if you add just propanone, the cress seeds are killed.
to find the % germination, count the number of seeds that have germinated. divide this by the no. seeds you start with and x by 100
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zizou
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#24
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#24
so waht do we use propanone or water as a solvent...coz the question says we shud use either....which we (students) have to decide
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rae
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#25
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#25
(Original post by zizou)
so waht do we use propanone or water as a solvent...coz the question says we shud use either....which we (students) have to decide
depends what inhibitor youre focusing on!!!
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zizou
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#26
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#26
oh...
well which solvent is good fow which inhibitor...the only inhibitor i know is ABA...or am i wrong....im getting confused.......ah......can u clarify? pls
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adamg
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#27
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#27
so you just mash the tomato up with propanone and water to make the extract? and then dilute that? do you need to use specific amounts of water and propanone? thanks
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Wilsoncswai
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#28
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#28
SO WHY PUT PROPANONE IN if its going to kill the seeds? we dont need the seeds, why dont we just add different amounts of water and make e.g.5 different concentrations, WHY propanone? how do we 'apply' them on cress seeds? please help
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adamg
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#29
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#29
ABA is soluble in propanone but not very soluble in water. Maybe you use a little bit of propanone in water to help make the extract, but not enough to kill the seeds?
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Wilsoncswai
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#30
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#30
how sure are you that ABA dissolves in propanone but not polar solvent water, coz i reckon is water soluble. WHy ABA anyway coz ABA is stress hormone, itsnt geribbrellin is one we are looking for coz it is responsible for stimulation of maltase and cell elongation.
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adamg
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#31
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#31
ABA is a 'lipid-type' hormone and websites like http://www.agscientific.com/Item/A1094.htm also say that ABA is only soluble in alcohol. It is probably soluble in water, just not very soluble. Gibberellins promote growth and in the plan it says its about natural inhibitors.
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crana
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#32
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#32
(Original post by adamg)
ABA is a 'lipid-type' hormone and websites like http://www.agscientific.com/Item/A1094.htm also say that ABA is only soluble in alcohol. It is probably soluble in water, just not very soluble. Gibberellins promote growth and in the plan it says its about natural inhibitors.
Hi
Just wondering something here - ABA is transported in the xylem and phloem - how is it transported if it's not really water soluble? it has quite a few polar groups, although I know it has an arene ring and also a hydrocarbon chain.. Also alcohols (unless they have very high molecular masses) are polar solvents surely?

a confused rosie
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Wilsoncswai
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#33
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#33
yes i would imagine ABA is dissolved in polar solvent. its not propanol, but PROPANONE< ketone, non-polar.e.t.c...
i still dont understant extracting germinating inhibitor (ABA) using propanone. i need the ROLE of propanone, i know it kills the seeds, but how exactly do we USE It, just to kill it? how to apply propanone to extract tomato juice.. i know the water is use to dilute concentration, now the only thing i need to know is propanone, please i need this last bit sorted.thanks everyone
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crana
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#34
Report 16 years ago
#34
(Original post by Wilsoncswai)
yes i would imagine ABA is dissolved in polar solvent. its not propanol, but PROPANONE< ketone, non-polar.e.t.c...
i still dont understant extracting germinating inhibitor (ABA) using propanone. i need the ROLE of propanone, i know it kills the seeds, but how exactly do we USE It, just to kill it? how to apply propanone to extract tomato juice.. i know the water is use to dilute concentration, now the only thing i need to know is propanone, please i need this last bit sorted.thanks everyone
please, PLEASE, just LISTEN and stop posting this!
THE PROPANONE IS NOT USED TO KILL THE SEEDS. THAT IS JUST SOMETHING THAT IT HAPPENS TO DO. IT IS USED AS A NON-POLAR SOLVENT TO DISSOLVE ANYTHING NON-POLAR IN THE TOMATOES YOU MAY WANT TO INVESTIGATE.

Alright?

By the way, ketones are slightly polar, and what on earth has propanol got to do with anything?

Rosie
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adamg
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#35
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#35
maybe you use propanone to extract the ABA, then use water to dilute it sufficiently so that it does not kill the seeds?
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crana
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#36
Report 16 years ago
#36
(Original post by adamg)
maybe you use propanone to extract the ABA, then use water to dilute it sufficiently so that it does not kill the seeds?
Did you see my post to you a couple of posts up?
Rosie
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adamg
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#37
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#37
what about it?
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rae
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#38
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#38
(Original post by crana)
Hi
Just wondering something here - ABA is transported in the xylem and phloem - how is it transported if it's not really water soluble? it has quite a few polar groups, although I know it has an arene ring and also a hydrocarbon chain.. Also alcohols (unless they have very high molecular masses) are polar solvents surely?

a confused rosie
ive got in my notes that ABA is primarily transported in the phloem. in my plan i put that this suggests it is polar which is how i justified using water for my solvent to avoid the obvious propanone issue!!!
looked up ethanol. it said it can dissolve both polar and non polar solvents. if you need more info on that pm me and ill type the paragraph up for you
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crana
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#39
Report 16 years ago
#39
(Original post by adamg)
what about it?
they were questions to you. but nevermind.
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crana
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#40
Report 16 years ago
#40
(Original post by rae)
ive got in my notes that ABA is primarily transported in the phloem. in my plan i put that this suggests it is polar which is how i justified using water for my solvent to avoid the obvious propanone issue!!!
looked up ethanol. it said it can dissolve both polar and non polar solvents. if you need more info on that pm me and ill type the paragraph up for you
Cheers I think I'm alright without that paragraph but thanks for the offer! I agree, I think it's polar too - agree about the ethanol, I think we have used it in chemistry mixed with water to help not-very-polar things dissolve. I was kind of trying to make the point that it being soluble in alcohol didn't make it non-polar, but I guess I didn't put it across well!

good luck with your coursework
rosie

ps. Im from nottingham too
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