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    I cba to do any maths or physics work seeing I got c1 ,c2 on 24 and ph1 and fp1 27th <_<. *sighs* I need some boost here!
    Not to mention on 27th I have to go all the way to B.ham from notownsville. =/
    As I am sitting my maths elsewhere and physics at the college.Just great
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    (Original post by ibysaiyan)
    Oops that blows. :p:
    :hubba:
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    (Original post by ibysaiyan)
    I cba to do any maths or physics work seeing I got c1 ,c2 on 24 and ph1 and fp1 27th <_<. *sighs* I need some boost here!
    Not to mention on 27th I have to go all the way to B.ham from notownsville. =/
    As I am sitting my maths elsewhere and physics at the college.Just great
    That's nasty! :console:

    But when the exams are over you have a great summer before uni :party:
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    (Original post by Remarqable M)
    Describe and explain Polymerase chain reaction? :p:
    Aww. Was beaten to it. But ah well...

    The Polymerase Chain reaction (PCR) is pretty much a method of artifical DNA replication. Small amounts of DNA can be replicated multiple times to produce larger amounts of DNA. This is particularily useful in forensic analysis, where there are only small amounts of DNA present, this can be amplified, so that enough is available to use for other DNA analysis methods such as DNA profiling or genetic finger printing.

    PCR makes several assumptions about DNA. First that it is made up of antiparrallel strands, that is has a 5 prime end and a 3 prime end, that it only grows from the 3 prime end, and that it pairs according to the complementary base pairing rules. (A with T and C with G).

    In PCR, the DNA polymerase enzyme that is used is derived from thermophillic bacteria. This works at an optimum temperature of 72 degrees.

    The DNA strands for replication are mixed with, free DNA nucleotides and DNA polymerase. The process operates on cycles of heating and cooling to break and bind the strands.
    Initially the temperature is 95 degrees, this breaks the hydrogen bonds between the DNA strands to produce single strands of DNA. The temperature is reduced to 55 degrees and primers are added to the mixture. These are single strands of nucleotide bases that consist of 10-20 base pairs. They bind to the sinlge strands of DNA to form partially double stranded DNA. The DNA polymerase can now bind onto the DNA, and nucleotide bases can be added to the DNA in the normal process. The temperature is increased to 72 degrees. When it reaches the end of the molecule the replication is complete.
    The process can be repeated multiple times, to expontentially increase the number of replicated DNA in the sample.

    There are several ways that PCR differs from normal DNA replication. It needs to make use of primers to initiate the replication process as DNA polymerase is unable to bind onto single stranded DNA. It relies on cylces of heating and cooling to break and bind strands of DNA, wheras in the normal process DNA helicase enzymes are used. And the process can only operate on short strands of DNA, unlike normal DNA replication (mitosis) that can operate on entire chromosomes.

    Sorry, I do go into all the detail I remember. :o:
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    (Original post by ViolinGirl)
    Aww. Was beaten to it. But ah well...

    The Polymerase Chain reaction (PCR) is pretty much a method of artifical DNA replication. Small amounts of DNA can be replicated multiple times to produce larger amounts of DNA. This is particularily useful in forensic analysis, where there are only small amounts of DNA present, this can be amplified, so that enough is available to use for other DNA analysis methods such as DNA profiling or genetic finger printing.

    PCR makes several assumptions about DNA. First that it is made up of antiparrallel strands, that is has a 5 prime end and a 3 prime end, that it only grows from the 3 prime end, and that it pairs according to the complementary base pairing rules. (A with T and C with G).

    In PCR, the DNA polymerase enzyme that is used is derived from thermophillic bacteria. This works at an optimum temperature of 72 degrees.

    The DNA strands for replication are mixed with, free DNA nucleotides and DNA polymerase. The process operates on cycles of heating and cooling to break and bind the strands.
    Initially the temperature is 95 degrees, this breaks the hydrogen bonds between the DNA strands to produce single strands of DNA. The temperature is reduced to 55 degrees and primers are added to the mixture. These are single strands of nucleotide bases that consist of 10-20 base pairs. They bind to the sinlge strands of DNA to form partially double stranded DNA. The DNA polymerase can now bind onto the DNA, and nucleotide bases can be added to the DNA in the normal process. The temperature is increased to 72 degrees. When it reaches the end of the molecule the replication is complete.
    The process can be repeated multiple times, to expontentially increase the number of replicated DNA in the sample.

    There are several ways that PCR differs from normal DNA replication. It needs to make use of primers to initiate the replication process as DNA polymerase is unable to bind onto single stranded DNA. It relies on cylces of heating and cooling to break and bind strands of DNA, wheras in the normal process DNA helicase enzymes are used. And the process can only operate on short strands of DNA, unlike normal DNA replication (mitosis) that can operate on entire chromosomes.

    Sorry, I do go into all the detail I remember. :o:
    wow nicely explained, i think you will get an A in f215:p: :p: so pcr is essentially DNA replication but on a smaller scale to produce multiple copies of DNA. I think I get the general picture now.

    do you know what the advantages are for using PCR compared to placing the desired gene in a bacterial plasma and get multiple copies of the same gene when the bacteria divides by binary fission?
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    (Original post by ibysaiyan)
    Hi there oh... now whats in module 2 again :/?I do other book which differs from heinmanns. :/
    :O You stole my question ¬_¬

    Nah, only joking. Erm, module 2 is all the biotech stuff, and genome sequencing etc, enzymes, cloning...

    Have a question? :p: I doubt. You know it all!
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    (Original post by Remarqable M)
    wow nicely explained, i think you will get an A in f215:p: :p:
    Hehe. I hope so. I need an A*.
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    (Original post by ViolinGirl)
    :O You stole my question ¬_¬

    Nah, only joking. Erm, module 2 is all the biotech stuff, and genome sequencing etc, enzymes, cloning...

    Have a question? :p: I doubt. You know it all!
    Hmm.... oh that stuff :/ cant always be 100% sure now can I ?lol err I will post up if anything bothers me. =}
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    (Original post by ibysaiyan)
    Hmm.... oh that stuff :/ cant always be 100% sure now can I ?lol err I will post up if anything bothers me. =}
    lol. I know.

    Sorry about your awful exam timetable =(
    I hope you manage to make it through it ok.

    And I was so complaining about mine, well some of it. The worst is:
    16th- Biology
    17th- Chemistry
    18th- Physics & C4

    Not looking forward to those days...
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    (Original post by ViolinGirl)
    lol. I know.

    Sorry about your awful exam timetable =(
    I hope you manage to make it through it ok.

    And I was so complaining about mine, well some of it. The worst is:
    16th- Biology
    17th- Chemistry
    18th- Physics & C4

    Not looking forward to those days...
    Oh good luck with those! I hope you get all 95%+ xD.
    yep 12 exams ftw! =}
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    (Original post by Remarqable M)
    wow nicely explained, i think you will get an A in f215:p: :p: so pcr is essentially DNA replication but on a smaller scale to produce multiple copies of DNA. I think I get the general picture now.

    do you know what the advantages are for using PCR compared to placing the desired gene in a bacterial plasma and get multiple copies of the same gene when the bacteria divides by binary fission?

    Well, the process of placing the desired gene into a bacterial plasmid is used for genetic engineering. I think the process would be inefficient for DNA replication, if you wanted access to the genes. Because the genes would be placed within the vector (the bacterial plasmid), and even though the can easily be replicated multiple times by then placing the plasmid into a bacterium such as E.coli, you would have to individually extract the genes from the bacterium.
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    (Original post by ibysaiyan)
    Oh good luck with those! I hope you get all 95%+ xD.
    yep 12 exams ftw! =}
    Wow, that sure would be lovely. Good luck too. What are you aiming for (grades)?

    At least you are pretty much done with your biology revision now. I have the whole of the last chapter to do.
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    (Original post by ViolinGirl)
    Wow, that sure would be lovely. Good luck too. What are you aiming for (grades)?

    At least you are pretty much done with your biology revision now. I have the whole of the last chapter to do.
    AA*A* or insurance: AAA* (
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    (Original post by ibysaiyan)
    AA*A* or insurance: AAA* (
    Woah. What are they?! Who wants A*A*A?
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    (Original post by ViolinGirl)
    Woah. What are they?! Who wants A*A*A?
    Scholarship :/ M.phy ICL.
    Again thats all under the condition I get it.
















    :/
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    I feel so this:
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    (Original post by ibysaiyan)
    Scholarship :/ M.phy ICL.
    Again thats all under the condition I get it.
















    :/
    Nevermind. I'm sure you will. :yep:
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    (Original post by ibysaiyan)
    I feel so this:
    Exactly. Urh..
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    Hey! ibysaiyan!

    Can you explain gene linkage to me please? (both normal, and sex linkage)

    And how do you do genetic diagrams when linkage is involved?

    :woo: :woo: :woo:
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    (Original post by ViolinGirl)
    Hey! ibysaiyan!

    Can you explain gene linkage to me please? (both normal, and sex linkage)

    And how do you do genetic diagrams when linkage is involved?

    :woo: :woo: :woo:
    Hi there,Lets see...
    Err do you mean like hpw do the gametes cross link with each other for instance in the punnet square?
    Oh I think i get it now...
    Sex linkage is where you get diseases or "Characteristics" exclusively on one type of chromosome.Say haemophilia which is an 'X' chromosome recessive allele.Note: X^hX^h fetus doesn't survive.
    Now one would think why don't women show these "characteristics" but just carry them? Reason well as we know our beautiful mums carry two X's as a result one dominates the other allele.
    Hope I made it clear on the sex-linkage bit? tbh I had it at first confused with the autosomal linkage.


    Genetic linkage:Is the estimate of how the recombination of alleles or genes undergoes during meiosis or to be specific inheritance.

    So the frequency of the crossing over or re-shuffling depends on how close the alleles/genes are.
    Say for example: We observe Gene A and Gene B together always.This probably means they are situated in the same chromosome close to each other so when segregation occurs there is "less" chance of them being displaces in the newly formed hybrid.
    For genes being physically apart there will be a greater or more likely chance of them being re-shuffled.

    Hope I made sense. =}
 
 
 
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