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ANSWERING ALL BIO/CHEM PAPER 1 DOUBTS :)

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I've tried to make a rough sketch of an example of crosses between a heterozygous and a homozygous recessive.. check it out!
okie...forget the ratio...we see that the grandparents are normal so there genotype is either TT or Tt...it should be Tt cuz when offsprings are showing 'abnormality' it means that by crossing we should get tt which is ONLY possible when the grandparents are Tt and Tt. get it?
 
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okie...forget the ratio...we see that the grandparents are normal so there genotype is either TT or Tt...it should be Tt cuz when offsprings are showing 'abnormality' it means that by crossing we should get tt which is ONLY possible when the grandparents are Tt and Tt. get it?
Sorry for bothering.. i know am asking a lot of questions. The question says that normal individuals are indicated by white symbols.. but the grand-parents are indicated by black symbols, showing that they have a defect. So how does it make them heterozygous, since they have an abnormality??
 
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Sorry for bothering.. i know am asking a lot of questions. The question says that normal individuals are indicated by white symbols.. but the grand-parents are indicated by black symbols, showing that they have a defect. So how does it make them heterozygous, since they have an abnormality??
it's completely fine...i don't mind :)
grandparents are normal..they are white not black :eek:
 
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it's completely fine...i don't mind :)
grandparents are normal..they are white not black :eek:
Grand parents are black! Check it out below..
amHJD.jpg
 
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this also why it is c not d
The removal of urea from the blood is not excretion, but a process of filtration carried out by the kidneys! By definition, excretion is the removal of waste products from the body (As in, out of the body). So the only answer here is the removal of undigested food from the anus (C). Hope this helped..
 
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The removal of urea from the blood is not excretion, but a process of filtration carried out by the kidneys! By definition, excretion is the removal of waste products from the body (As in, out of the body). So the only answer here is the removal of undigested food from the anus (C). Hope this helped..
i know but in the mark scheme it is the removal of urea from kidney
 
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i know but in the mark scheme it is the removal of urea from kidney
Oh yeah.. I was wrong! Did some research now.. removal of undigested food from the anus is egestion. Removal of urea from the blood is excretion coz urea is a waste product. Thank u for clarification btw, I would've gt it wrong tomorrow! :p
 
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Oh yeah.. I was wrong! Did some research now.. removal of undigested food from the anus is egestion. Removal of urea from the blood is excretion coz urea is a waste product. Thank u for clarification btw, I would've gt it wrong tomorrow! :p
thank you also very much ;)
 
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Water will diffuse through the potato into the concentrated sugar solution. This is because osmosis/diffusion occurs from a region of high concentration to a region of lower concentration (down the concentration gradient). Hence, the water will move into the concentrated sugar solution (since there are more water molecules outside the potato) and its level will decrease while the level of sugar soln will increase. So the answer here is C..
 
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Hi again...now almost Im done with igcse's questions 1994-2011 (almost)....lets go bk to o-level questions...
the one u explained it to me yesterday actually I didn't get it well about muscles longitudinal which u said to me antagonistic...plz reexplain it to me again and thanks
umm...can you please quote the post where i replied?
 
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