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    However, I did say Globular are spherical and round,.... which is a comparison...should get a mark
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    (Original post by LyreBirds)
    Yeah in the syllabus it comes under Topic 6:
    4. Explain how one gene can give rise to more than one protein through post-transcriptional changes to messenger RNA.
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
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    (Original post by Fuego1)
    What were the two substrate molecules for 1 mark? I guessed Rubp and co2 but surely co2 isn't a substrate since it's a gas??
    thats exactly what i wrote and still think
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    (Original post by cmolloy12)
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
    ooh i kinda put that, haven't seen anyone say that. Thats kinda reassuring....
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    (Original post by cmolloy12)
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
    Really? The IAL January 2014 paper had a similar question if I remember.
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    (Original post by cmolloy12)
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
    Question wasn't specifically asking why they would be of different lengths, it was asking more abt how different proteins could made from a single gene so it is perfectly appropriate to discuss post transcriptional modifications. That will be one of the main points for definite. Also, genes were not different lengths, the proteins were, the gene coding for the different proteins was exactly the same.
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    (Original post by hopefuldentist10)
    Whoopsie, I didn't revise exons/introns. I spliced my score by 6 marks there.

    Dropped maybe 20-25 marks in that paper, I have no idea. Just little marks here and there, eg. saying "cellulose is beta" instead of "beta glucose".

    Considering many people thought it was an awful then the grade boundaries will get me on an A* hopefully. Hooray for dumbed down education.
    you may be in luck for the 6 mark cos a key part of the question said the genes were different lengths which would lead to different primary sequences and therefore different proteins
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    (Original post by cmolloy12)
    thats what i got for the % but i can't remember the other question what was it
    It was the difference in the body temperature, which I calculated to be 1.23
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    (Original post by greenorange)
    I did trophic level 3 divided by trophic level 2, after I subtracted total energy in from energy out.
    yea it was 70/800 x 100 the method for this equation is in the revision guide
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    I remember it saying different protein lengths, but not different gene lengths? Wouldn't be the first brain fart I made on that paper if so lol
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    (Original post by sssssshh)
    It was the difference in the body temperature, which I calculated to be 1.23
    How many marks was that worth?
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    (Original post by greenorange)
    I measured from the highest point to the lowest, maybe 1.75-I honestly can't remember.
    yea thats what i did i think loads of people were caught out and measured greatest increase and not change
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    (Original post by MrSheeple)
    I remember it saying different protein lengths, but not different gene lengths? Wouldn't be the first brain fart I made on that paper if so lol
    Nah you are right, his explanation was wrong, it wasn't genes of different lengths, it was proteins of different lengths, the explanation talking about post transcriptional modifications is correct.
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    (Original post by cmolloy12)
    yea it was 70/800 x 100 the method for this equation is in the revision guide
    Im sure it asked about percentage availibe to level 4 from level 2 so it would be 70(energy available from level 3)/2300(energy in at level 2) x100 which is where we are getting 3% from.
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    (Original post by Ladymusiclover)
    How many marks was that worth?
    Not too sure, but I think it was 3
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    (Original post by sssssshh)
    Not too sure, but I think it was 3
    I think the trophic level question was 3 marks but I thought the other calculation was max. 2 marks.
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    (Original post by cmolloy12)
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
    I disagree with your point. I think post transcriptional changes would have been credited.
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    (Original post by Ladymusiclover)
    I think the trophic level question was 3 marks but I thought the other calculation was max. 2 marks.
    Yeah I think you're right.
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    (Original post by cmolloy12)
    a lot of people fell into this trap and got dragged into talking about splicing but the key point was that the genes were different lengths and would therefore have different amino acids primary sequences, giving rise to different proteins
    How do you propose different lengths of proteins are made aside from due to splicing and post transcriptional changes, if the same gene is used? I'm pretty sure they said the proteins were coded for by the same gene. Can't be entirely sure tho.
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    (Original post by Nemo9000)
    Im sure it asked about percentage availibe to level 4 from level 2 so it would be 70(energy available from level 3)/2300(energy in at level 2) x100 which is where we are getting 3% from.
    Think (hope!) you are supposed to compare NPP levels each time ...i.e. NPP of one level divided by NPP of previous level multiplied by 100 = 8.75% ..... *fingers crossed*
 
 
 
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