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ok then how these mean mass r different for diff. light intensity?
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A2 Biology | Post your doubts here
- Thread starter hassam
- Start date
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_qp_51.pdf
q2 last part...y cnt we use infected liver of mass to obtain plasmodium
q2 last part...y cnt we use infected liver of mass to obtain plasmodium
its b/c they are different types of leaves.......well leave it....cn u elaborate on the dry mass thing a bit more....how water will effect reading
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since we r investigating indirectly the rate of photosynthesis with the light intensity...we have to concider the dry mass that how much mean mass was increased or decreasd due to light intensity...if we dont consider the dry mass then the exp. will be wrong as even the water potential will play a roll for change in the mean mass that is y even in the table they calculated the rate of water loss per hr...coz at high light intensity the leaf will be having less water potential due to high rate of transpiration and viceversa...ok this is my assumption but i might be wrong ...so if u know it better plz explain me
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_qp_51.pdf
q1 a ii...dont u feel ms is wrong when saying methid of varying light intensity....cos question dint aked to vary it just asked to measure rate at low intensity for both leaves
q1 a ii...dont u feel ms is wrong when saying methid of varying light intensity....cos question dint aked to vary it just asked to measure rate at low intensity for both leaves
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lol..no...its absolutly correct..read the first sentence of the Q and the student's hypothesis...based on that we have to write our exp..and we have to vary light intensity in a dark room...
Leaf discs from shade leaves will photosynthesise at a higher rate in low light
intensity than leaf discs from sun leaves. ????
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for sun leaves light intensity will be limiting the rat e of photosynthesis....
but shade leaves will adapt them to photosynthesis in low light intensities as they grow in such conditions..........
well can u explain me what is meant by overlapping in error bars?????????????wts is its significance..............plz
but shade leaves will adapt them to photosynthesis in low light intensities as they grow in such conditions..........
well can u explain me what is meant by overlapping in error bars?????????????wts is its significance..............plz
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coz its adapted to low light intensity...so higer rate at low light intensity...
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overlapping means the 2 means r not signeficantly different...
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means that result is not reliable......and can u ellaborate more plz thanx in advance...........
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ok wat does da significance mean? pz explain
Statistically significant result are those that are not due to chance bt there is reason.....e.g there is difference b/w no. of stomata in shade and sun leaves if i do random sampling....now if my results are not siginificant ...then this means that the numbers in two grupps are not too much different and are different just due to chance
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oh oki thnx
??????????
i was saying the question doesnt say to vary light intensity....bt u said it did so???coz its adapted to low light intensity...so higer rate at low light intensity...
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look we r taking two types of leaves, 1 from shaded and 1 exposed to light...now our hypothesis is to campare which 1 will photosynthesys more at lower light intensity...so dont u think when u want to carry out this hypotheis u have to vary light intensity in a dark room coz there shouldnt be any other kind of light source around ....ok then how u will come to know that what will be the photosynthsis rate at high light intensity for the shaded leaf.?
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ohh GOD M/J 51 suxxxx
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here they just want to know the rate of photosynthesis ...higher rate means more volume of O2 and the leaf will rise up faster as it experiences upthrust force due to more volume of O2...so they showed the method how to take leaf discs from both types of leaves...they took a syringe, removed the plunger, placed the finger over the open end of the syringe, pored the NaHCO3 solution and then 6 leaf dics in the solution,...now they put the plunger back, put the syringe upside down , means the needle part up...then pushed the plunger upword till all the air comes out, den placed the finger on top of the needle part and pulled the plunger to creat a vaccum, tapped the side of the syringe to remove all the air bubble,till the leaf discs sunk to the bottom- means therez no gas around the disc..as soosn as the disc sink start the timing till it rises up...this time gives us the rate of O2 production during photo..the higher the rate the faster it will rise up and the lesser time it will take...