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A level Biology: Post your doubts here!

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A*****
No they can't directly or by themselves. But they can neutralize toxins, or can cause clumping of bacteria or viruses so immobilizing them making it easier for *macrophages* to destroy them
 
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According to mark scheme, the impulses first reach the apex of the heart and then through the purkyne tissues...then what about those tissues which are above the apex?
It moves from P - down to apex - then moves bottom up through purkyne tissues
 
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They have a variable region with antigen binding site so can cause agglutination of antigns/pathogens or may result in opsonisation or act as antitoxins
A*****
No they can't directly or by themselves. But they can neutralize toxins, or can cause clumping of bacteria or viruses so immobilizing them making it easier for *macrophages* to destroy them

So can we just generally write that antibodies destroy pathogens, as is written in this mark scheme?
 

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The usual. Questions were in the same style as every paper, after 2016, out there.
yh true that
tho i did lose 2 marks in one question lol (wrote abt glycolysis in the one abt cancer cells using up an amino acid to make a 5C compoud *sigh*)
but the rest went well
 
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i did like 4x4(so like 16 boxes in total) because werent there like 4 alleles each like FG fg fG and Fg as they were the offspring of F1 generation
They said (considering there is no crossing over)
so it meant that the gametes formed were (FG) and (fg) since they didn't tend to independently assort
 
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