Qualification > Sciences
IGCSE Biology Paper 3
sheshee:
--- Quote from: shafiq_92libra on June 09, 2009, 11:52:54 am ---chem was definately better dan bio for me ><
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uhhhh rlyyy nooo for me bio ws much easier than chem omg chem ws somthin different :-\
aquarian93:
i sed when there's a cut, platelets and damaged tissues secrete chemicals which converts a soluble protein fibrinogen to insoluble fibrin which forms fibres, and a mesh which forms a clot.
girl_92:
--- Quote from: nid404 on June 09, 2009, 05:47:24 am ---
--- Quote from: Friends on June 09, 2009, 05:41:48 am ---
--- Quote from: nid404 on June 09, 2009, 05:39:38 am ---the water that the plants have taken up is not the only wet mass they have. The water has to be removed completely
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Yeah I know.
But as they used the same raddish for 6weeks. We cannot dry it. So the Best option Would be what we wrote.
;D ;D ;D ;D ;D
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who said the radish used is the same for the weeks. It's not possible...and im sorry cuz to find out dry mass u need to kill the organism.
I'll put down exactly what the book says..take a look
Dry mass is often used as a measure of growth, because wet mass varies from day to day. The value for dry mass is obtained by drying out the organism in an oven, but this involves killing it.
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yea nid i wrote the same i wrote dry it in an oven n den weighit using a measurin balance am i correct
girl_92:
--- Quote from: Friends on June 09, 2009, 06:13:07 am ---
--- Quote from: Mirzaa on June 09, 2009, 06:07:04 am ---
--- Quote from: thukon on June 09, 2009, 05:48:41 am ---
--- Quote from: Mirzaa on June 09, 2009, 05:45:12 am ---
--- Quote from: thukon on June 09, 2009, 05:27:16 am ---Liver cells - Nucleus, Cytoplasm, and cell membrane. I hope.
Yeah, hepatic portal vein and ileum
dry mass, i put measure the amount of solution uptaken by the plants., and then subtract from original. I think its wrong.
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yea thats wrond dude.... uve gotta bake the radish plant to find the dry mass..!
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But the same radish has to be used for 6 weeks. How would you "bake" it without killing it? Thats what the
experiment says nid. They measure the growth of the plant for 6 weeks. They wont use different plants.
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it says in the Hodder Murray revision guide, By the way, so it s gotta be rite. theres no 2 ways about it, to find the dry mass uve gotta bake the organism, even if cells denature etc etc
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As the plant can't make WATER, they have to absorb it from the solution. So if U subtract the mass of water absorb from the mass of radish u get the dry mass.
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hey not necesarrily the cells have water frm b4 as well dey need more water to promote further growth so for the dry mass u need to completely dry it out
aquarian93:
lemme think
i got the dry mass thing rong cuz i jus sed withdraw the water from the plant.
and the enzyme bacteria thing i rote use a fermenter, starch soln is the source, and a water jacket to make the temp constant, dunno if ill get all 3 marks tho ???
and u noe da 3 reasons why the energy decreases from the plants to animal quesiton i think ill lose 1 mark.
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