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    Im confused about how exactly they differ
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    (Original post by Chemistrybuddy)
    Im confused about how exactly they differ
    Strands of DNA are wound around histone proteins making up chromosomes
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    (Original post by Hunnybeebee)
    Strands of DNA are wound around histone proteins making up chromosomes
    So say in a genetic material hierarchy Chromosomes are above DNA? Chromosomes contain genes rather than DNA containing genes?
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    (Original post by Chemistrybuddy)
    So say in a genetic material hierarchy Chromosomes are above DNA? Chromosomes contain genes rather than DNA containing genes?
    Genes are a section of DNA (that code for a polypeptide). You're almost correct, the 'hierarchy' will go as

    (smaller end) genes are in --> DNA, are in --> Chromosomes (larger end)
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    [QUOTE=Hunnybeebee;63771341]Genes are a section of DNA (that code for a polypeptide). You're almost correct, the 'hierarchy' will go as

    (smaller end) genes are in --> DNA, are in --> Chromosomes (larger end)[/QUOTE

    Could you also clear this up for me please- in my book it says the genetic code is a triplet code where three nucleotide bases code for an amino acid, and then it says there are four bases pranged in groups of three?
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    I'll try the best I can. Your definition of a genetic code is correct, a triplet code is 3 bases that codes for one amino acid, ie AUG = Methionine, but I've never heard of four bases pranged in groups of 3 I'm afraid, I'm on OCR A2 so if you're doing the same let me know as I may need to learn it for the exam
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    (Original post by Hunnybeebee)
    I'll try the best I can. Your definition of a genetic code is correct, a triplet code is 3 bases that codes for one amino acid, ie AUG = Methionine, but I've never heard of four bases pranged in groups of 3 I'm afraid, I'm on OCR A2 so if you're doing the same let me know as I may need to learn it for the exam
    I am doing OCR A2 aswell. Go onto page 104 and read the first bullet point under the heading 'genetic code'
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    (Original post by Chemistrybuddy)
    I am doing OCR A2 aswell. Go onto page 104 and read the first bullet point under the heading 'genetic code'
    oh my i really am missing something. Is this cellular control? I'm using the cambridge green book, not the endorsed one I'm afraid, but looking through the specification the other day, I haven't seen that point at all..
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    (Original post by Hunnybeebee)
    oh my i really am missing something. Is this cellular control? I'm using the cambridge green book, not the endorsed one I'm afraid, but looking through the specification the other day, I haven't seen that point at all..
    The specification is of course not going to contain all the points you need to know. I would use the OCR book as its specifically from the exam board.
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    (Original post by Chemistrybuddy)
    The specification is of course not going to contain all the points you need to know. I would use the OCR book as its specifically from the exam board.
    loooooool alright then hahah
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    [QUOTE=Chemistrybuddy;63771769
    Could you also clear this up for me please- in my book it says the genetic code is a triplet code where three nucleotide bases code for an amino acid, and then it says there are four bases pranged in groups of three?[/QUOTE]

    (Original post by Hunnybeebee)
    I'll try the best I can. Your definition of a genetic code is correct, a triplet code is 3 bases that codes for one amino acid, ie AUG = Methionine, but I've never heard of four bases pranged in groups of 3 I'm afraid, I'm on OCR A2 so if you're doing the same let me know as I may need to learn it for the exam
    Badly worded phrase. Three nucleotides make up a triplet (codon), which codes for one amino acid. Those three nucleotides can be any of the four nucleic acids ATCG/AUCG, depending on whether it is DNA, or mRNA, respectively. Eg ATG, AAA, ATT etc. In essence, there are 64 possible combinations of codons.
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    (Original post by Chemistrybuddy)
    Im confused about how exactly they differ
    A gene is a recipe for a protein, and DNA is the recipe book (a strand of DNA contains many genes). A chromosome is a load of DNA all wound up into one compact space.

    Another analogy: DNA is a piece of string, a chromosome is the ball of string.

    As for the base pairs: in DNA (specifically "DNA", not "RNA"), there are 4 bases: A, T, C and G. They line up in a string (i.e. a stand of DNA), something like AAGCGGCAAATTGCACGTGACTA... etc. (I just made that sequence up, it's not important).

    They get "read" in groups of three, each group of three codes for a specific amino acid (and the many amino acids together will make a protein).

    (FYI, RNA also has 4 bases, but one of them is different. Also note that the bases of DNA and RNA don't line up on their own, but in "base pairs"... don't know if you're interested in knowing that so I won't go into it).
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    To put it simply:
    Chromosomes carry genes, which are made from DNA.
 
 
 
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