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A level Biology: Post your doubts here!

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Don't worry. Friend of mine prepared A LOT and he said the exam, also variant 22, was freaking hard. I think the grade boundaries will be lower maybe 45 for A. I wonder how difficult 42 is gonna be
I think the grade boundary will be high becuz in may/june session most of the school candidates are giving the exam and there is more competition.Lets c lets hope for the best. :)
 
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How was the paper everyone?



I too think it would be around 35, Last year's paper was way too easier. I have never seen paper of this level before!
And time management disturbed me too, but Alhamdulillah i didn't left any.
They have never asked some of these questions before. Ever. Expect a lower boundary coz I don't think everyone would have done well in the new questions. I did :p
 
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Hello guys can anyone write a small summary for me about the most important points of biological molecules as i didnt have enough time to study it.Thanks in advance :)
 
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I have a couple of doubts regarding Evolution:
1. Explain how all organisms can potentially overproduce.
2. describe the processes that affect allele frequencies in populations with reference to the global distribution of malaria and sickle cell anaemia.
 
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I have a couple of doubts regarding Evolution:
1. Explain how all organisms can potentially overproduce.
2. describe the processes that affect allele frequencies in populations with reference to the global distribution of malaria and sickle cell anaemia.

Second question is about natural selection.
As one phenotype is favored, their allele frequency will increase. For eg: In the areas where malaria is common we see more people with sickle cell anaemia as this phenotype is at a selective advantage (Malarial parasite affects healthy RBCs not SCAnamic RBCs)
However, in the areas where Malaria is not common SCAnamic alleles are at selective disadvantage. So SCA allele is less in these places.
 
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Second question is about natural selection.
As one phenotype is favored, their allele frequency will increase. For eg: In the areas where malaria is common we see more people with sickle cell anaemia as this phenotype is at a selective advantage (Malarial parasite affects healthy RBCs not SCAnamic RBCs)
However, in the areas where Malaria is not common SCAnamic alleles are at selective disadvantage. So SCA allele is less in these places.
Ah, I see... Thanks
 
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