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    (Original post by ImBear)
    For the last question I believe the aorta and pulmonary artery were on the wrong sides of the heart, this is why the hole saved the babys life, de oxygenated blood could move across into the left (their left) ventricle and be pumped to the lungs, and oxygenated could move into the right ventricle to be pumped into the aorta to be pumped around the body

    Anybody else get this?
    I have thought about this and I think this is right. But unfortunately I was running out of time and didn't write it down. I just wrote the heart muscle could get enough oxygen to contract and pump blood to body. I wish i could get 1 mark for this one. Did the last 6 marks question related the hole or it is independent?
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    Yeah that paper was interesting, i also wrote that the pulmonary and aorta were on different sides, then the question after that were it asked why the baby didnt die i wrote that the blood pressure could be spread out or something since there was a hole in the septum i cant remember exactly , i missed out a 4 marker as i saw i was running out of time and wanted to answer the 6 marker.

    andd the question about the composition of starch i wrote that amylopectin has 1-4and 1-6 glysodic bond so energy can be released quicker than amyylose as it only has 1-4 glycosidic bonds so its straight chained.

    the adenine one i crossed 9000 because i took 4050x2 from 27000 and divivided it by two and 9000 was the closest although im not sure.

    i wrote exocytosis for one of the reactions
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    Hey guys, so for our upcoming edexcel exam about plants and development, do we need to know about the structure of a seed? In thw textbook it talks about it...but i dont know if we need to know it?
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    (Original post by THESTRESS)
    Hey guys, so for our upcoming edexcel exam about plants and development, do we need to know about the structure of a seed? In thw textbook it talks about it...but i dont know if we need to know it?
    According to the spec, all we nee to know is "how the uses of plant fibres and starch may contribute to sustainability, including plant-based products to replace oil-based plastics" and the methods of seed banks in the conservation of endangered species and their genetic diversity.

    In other words, I don't think we need to know too much detail about them
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    Okkkkk thanks everyone!!
    Another question, i dont really understnd what we are supposed o know about stem cells, as in this part 'Be able to discuss the way society uses scientific knowledge to makedecisions about the use of stem cells in medical therapies'


    Like what are the key ideas, its quite vague and i dislkie vagueness


    Also do any of you know about the acetabularia experiment? Are we supposed to know it?
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    (Original post by THESTRESS)
    Okkkkk thanks everyone!!
    Another question, I don't really understand what we are supposed to know about stem cells, as in this part 'Be able to discuss the way society uses scientific knowledge to make decisions about the use of stem cells in medical therapies'


    Like what are the key ideas, its quite vague and i dislkie vagueness


    Also do any of you know about the acetabularia experiment? Are we supposed to know it?
    Ok, my guess is that what you have referred to includes understanding the ethics behind the use of stem cells and how the government controls the study of stem cells (i.e. what regulations have been put in place to control stem cell research).

    You probably also should know how pluripotent cells can be used to replace damaged tissue (i.e. the stem cells are stimulated by surrounding cells which activates certain genes leading to transcription and translation etc etc)

    Just researched that experiment, yes, it is mentioned in the textbook (Hammerling's experiment) because it helps us understand the role of the nucleus in controlling the development of the inividual cell and the whole multicellular organism's phenotypes because the rhizoid (NOT the hat or stalk) contained the nucleus.
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    Riiiight Thank You for the the help (and the research).

    Soz for so many questions.....but, in methylation/acetylation, is it that one makes the gene inaccessible while the other makes it accessible. The idea i get is that methylation tightens the gene whereas acetyl loosens it?
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    (Original post by THESTRESS)
    Riiiight Thank You for the the help (and the research).

    Soz for so many questions.....but, in methylation/acetylation, is it that one makes the gene inaccessible while the other makes it accessible. The idea i get is that methylation tightens the gene whereas acetyl loosens it?
    Yes, DNA methylation is when methyl groups attach to the cytosine base which means that the DNA can't be transcribed. I didn't think acetyl groups loosened it though...I thought it had the same effect as methyl groups.
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    (Original post by imogenr)
    Yes, DNA methylation is when methyl groups attach to the cytosine base which means that the DNA can't be transcribed. I didn't think acetyl groups loosened it though...I thought it had the same effect as methyl groups.
    My textbook made it confusing, so i had to do some research and it suggested that dna methylation tightens the dna, and histone modification via acetyl loosens it. The i saw in my CGP revision guide that it does just that. Also if you look at this link on ggogle images it shows it https://www.google.co.uk/search?q=dn...X-w83LUagjM%3A
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    Hi do we need to know about the frog experiment on early/ late frog blastula?
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    And do we need to know the exact process for melanin production? Or just how environment can affect it? And do we need to know about transpiration?
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    (Original post by Alevelz)
    And do we need to know the exact process for melanin production? Or just how environment can affect it? And do we need to know about transpiration?
    I think it is safe to know both of them. I think definitely how melanin is made, they coud ask you to incroporate how the environment effects it, and jst to be safe about the frog bastulla (im thinking this is about the complimentary mrna and dna/mrna hybrid)

    And transpirationa quick run through covering the maun principles like cohesion,adhesion, root pressure etcc..
 
 
 
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