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Applying to Uni? Let Universities come to you. Click here to get your perfect place 20-10-2014
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    Is this book recommended for A Level Biology?
    http://www.amazon.co.uk/gp/product/0...A3KK0S74UJZEWZ
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    (Original post by Id and Ego seek)
    Is this book recommended for A Level Biology?
    http://www.amazon.co.uk/gp/product/0...A3KK0S74UJZEWZ
    No, it depends on the school and exam board
    a good one for OCR is OCR biology heinmann

    or advanced biology micheal kent for all exam boards AS and A2
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    (Original post by Id and Ego seek)
    Is this book recommended for A Level Biology?
    http://www.amazon.co.uk/gp/product/0...A3KK0S74UJZEWZ
    Advanced Biology by Jones and Jones is excellent!

    Didn't realise it was that expensive though!
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    can someone help me with my thread, so far i have 149 views but no reply ):
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    (Original post by thegodofgod)
    Advanced Biology by Jones and Jones is excellent!

    Didn't realise it was that expensive though!
    Cheers mate!

    Haha, the price is fine. It'll be worth it at the end :teehee:
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    (Original post by aceySnicks_x)
    can someone help me with my thread, so far i have 149 views but no reply ):
    Which thread? :erm:
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    Hello!
    I would love to join our society. I'm interesting and fascinating about biology and other natural sciences! So Introduce myself!

    Name: Gregorius alias Kallisto
    Hobbies: reading, art, martial art, sport (mainly martial art ), natural science (physics, biology and chemistry of course)
    Where you live: Anywhere in Germany
    Current Studying level: Studying for my life and an A-level at the moment!
    What you are studying: natural sciences (physics, biology and chemistry), languages (German, English and Latin) and social sciences (history and politic/economy) - these are my subjects.
    Hero(s): Gregor Mendel is one of my hero in biology: he has discovered the mendelian inheritance which were an important step in genetics in my opinion!
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    I'm wonder why there is no a member who is writing in this topic. Okay, it's my turn again!
    I'm reading doctrines about molecular genetics. I want to know what happen by a glycosidic bond. Why is it so important for DNA? Please answer in a short comment, if it's possible.
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    (Original post by Kallisto)
    I'm wonder why there is no a member who is writing in this topic. Okay, it's my turn again!
    I'm reading doctrines about molecular genetics. I want to know what happen by a glycosidic bond. Why is it so important for DNA? Please answer in a short comment, if it's possible.
    Hi, a glycosidic bond is formed by a condensation reaction (one water molecule is lost), just like when two glucose molecules condense to form one molecule of maltose.

    The opposite of a condensation reaction is a hydrolysis reaction, which is where one molecule of water is added to a compound, which splits it into two, e.g. maltose + water --> 2 glucose.

    One nucleotide (the repeating unit of any nucleic acid, e.g. DNA, RNA) is joined up to another via a glycosidic bond. Also, each part of a nucleotide (the pentose sugar, the organic base, and the phosphate group) is linked by a glycosidic bond.
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    (Original post by thegodofgod)
    Hi, a glycosidic bond is formed by a condensation reaction (one water molecule is lost), just like when two glucose molecules condense to form one molecule of maltose. (...)
    Hmmm... that sounds after an esterification as in a reaction between deoxyribose and phosphoric acid in this case. One water molecule is lost as well by this reacton. That's why I think a glycosic bond is also an esterification. That makes sense, because a condensation reaction IS an one. Am I right?
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    (Original post by Kallisto)
    Hmmm... that sounds after an esterification as in a reaction between deoxyribose and phosphoric acid in this case. One water molecule is lost as well by this reacton. That's why I think a glycosic bond is also an esterification. That makes sense, because a condensation reaction IS an one. Am I right?
    Esterification is different as it has the following group:

    O
    ||
    C-O-R
    |
    R

    , whereas a glycosidic bond has the following group:

    ....R.....R
    ....|......|
    R-C-O-C-R
    ....|......|
    ....R.....R
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    Hello fellow Student Room Users
    I really need some help with a question im really puzzled with
    The question is
    Our Genetic information is stored in nitrogenous bases in our DNA, using examples explain how these nitrogenous bases code for amino acids and how the sequence of amino acids code for a poly peptides

    I would be very grateful if someone can help me answer this question.
    Thank you all
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    (Original post by A-d-S10)
    x
    So I have got informations in terms of nitrogenous bases. there are two of them.
    In the one hand there is purine which has adenine (A) and guanine (G) as bases. In the other hand ther is pyrimidine which has cytosine (C) and thymine (T) as bases. An amino acid consists of three bases, as in lysine which has adenine three times. That's why it must be purine in my consideration. "sequence of" means a chain of protein which consist of amino acids. One example is:
    lysine (AAA) - proline (CCC) - glycine (GGG) - and so on... in this case we have purine, pyrimidine and purine in that order. I hope I was able to help you.
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    (Original post by Kallisto)
    So I have got informations in terms of nitrogenous bases. there are two of them.
    In the one hand there is purine which has adenine (A) and guanine (G) as bases. In the other hand ther is pyrimidine which has cytosine (C) and thymine (T) as bases. An amino acid consists of three bases, as in lysine which has adenine three times. That's why it must be purine in my consideration. "sequence of" means a chain of protein which consist of amino acids. One example is:
    lysine (AAA) - proline (CCC) - glycine (GGG) - and so on... in this case we have purine, pyrimidine and purine in that order. I hope I was able to help you.
    Thank you very much for your help
    I do however need help with a Codon Question i really need help with
    It involves a codon wheel
    Can you help me please ?
    I can Pm you the worksheet
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    (Original post by A-d-S10)
    Thank you very much for your help
    I do however need help with a Codon Question i really need help with
    It involves a codon wheel
    Can you help me please ?
    I can Pm you the worksheet
    Of course, I can help you. What is the exactly problem? Have you difficulties in determination of amino acid? What do you have to do? give me an answer, please!

    By the way I hope my last answer was right in this way. I'm not sure, but it made sense in my point of view.
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    (Original post by Kallisto)
    Of course, I can help you. What is the exactly problem? Have you difficulties in determination of amino acid? What do you have to do? give me an answer, please!

    By the way I hope my last answer was right in this way. I'm not sure, but it made sense in my point of view.
    Iv sent you a PM Kallisto
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    Hello there. I've just recently joined the group, and I have a few questions.

    I'm finishing by GCSE's, and I've chosen to do Biology for A-Level next year. My Biology Teacher has given me a letter about a 2 day residential field trip for the 25th and 26th of June. It is supposed to be ideal preperation for the first exam in A2 Biology and the ISA exam, as well as a good thing to mention when applying for a Uni.

    I was a bit overwhelmed that the A-Level Biology trip is so soon, I mean my last GCSE Exam (Geography) is on the date that we actually leave to go on this A-Level trip! I was wondering whether you guys have done something like this, or if you are doing something like this, and whether you can tell me anything else about it and what should we do if anything to prepare for it.
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    (Original post by Dobrzynski)
    Hello there. I've just recently joined the group, and I have a few questions.

    I'm finishing by GCSE's, and I've chosen to do Biology for A-Level next year. My Biology Teacher has given me a letter about a 2 day residential field trip for the 25th and 26th of June. It is supposed to be ideal preperation for the first exam in A2 Biology and the ISA exam, as well as a good thing to mention when applying for a Uni.

    I was a bit overwhelmed that the A-Level Biology trip is so soon, I mean my last GCSE Exam (Geography) is on the date that we actually leave to go on this A-Level trip! I was wondering whether you guys have done something like this, or if you are doing something like this, and whether you can tell me anything else about it and what should we do if anything to prepare for it.
    If the college you go to is anything like mine then you'll have the option to go after your AS levels and before A2 starts. Ours was about late June/early July last year, after our AS exams. Personally I wouldn't know if the trip helps. I never went and I got an A in the January exam this year.
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    (Original post by NessEB)
    If the college you go to is anything like mine then you'll have the option to go after your AS levels and before A2 starts. Ours was about late June/early July last year, after our AS exams. Personally I wouldn't know if the trip helps. I never went and I got an A in the January exam this year.
    Thanks for the reply. I've figured it would be a good experience nonetheless though.
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    Hi, I´d like to ask: Is Hamilton´s rule specifically used only for when one individial helps/saves exactly one individual (rB > C)? I got across the example when one brother saves the other one from drowning. The rule was applied like this: B=2 (average number of offspring for humans), r=0.5 (since they are brothers) and C = 0.25 (probability the brother will drown if the other will not save him) times 2 (the number of expected offspring if the altruist had stayed on the shore). Thus, it is beneficial for one brother to save the other. But, what would happen if two of his brothers were drowning (and he could save both)? I realize that if it is beneficial to save one, then it follows that it is advantageous to save both (if trying to save the second, does not endager them all - again, assume both can be saved), but how would the rule be applied? How would it be like mathematically?

    When it comes to the cost of "the provider", you can figure out the average probability they both will die, but how would “the-benefit-to-the-recipients” side of the inequality look like? Because, I don´t think you can just sum it up (r1B1 +r2B2; B1=B2) (or, to say it differently, multiply the benefit of one brother by two) as 50% of genes they share with the altruist is (if only in the minor part) different set of 50% (yes, r1 and r2 are both 0.5 mathematically, but when comparing "the biological character" = gene content of what r1/r2 respresent, then they are not the same). Thus – if we think of drowning brothers in the terms of genes, the altruist will – in total – save more than 50%…be it even 50.00000001%…

    We don´t even have to consider this ("drowning") example - I am simply interested in the maths of Hamilton rule when "the altruistic act" of an individual saves more than one individual (for this purpose, all of them can be siblings of the altruist).

    So? I am curious to know how this works...

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