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    WOOOOOOOOOOOOOOOOOOOOOOOOOP IM DONE WITH EXAMS!!!!!
    chem 5 c4 and bio 5 in the last 3 days!
    WOOOP IM DONE!
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    (Original post by sofja26)
    Hey I did the exact same thing as you I feel as if I read it completely wrong now I spoke about: Oestrous cycle, cell division, mitosis, genetic variation, antibiotics, mutations,cancer, protein synthesis. I am so gutted I actually cried about it BUT, I have looked at other peoples answers and some of our answers (from your post) is similar or the same. Yes this is 25 marks but surely we have to get some marks for these answers they cannot be 100% irrelevant. I am so so annoyed with myself, other people in my class spoke about ecology for this question

    I'm also looking at all biol 5 mark scheme essay answers; there are like 18 different points involved in this answer so who knows maybe we've just answered the unpopular ones but still got it right :/ :/
    Can't you still get like most of the marks for the question though and in the worse case you'll lose 3 marks for relevance?
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    (Original post by emilya1)
    Histamine is on the spec
    Thank you x


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    (Original post by sofja26)
    Same here I wrote about the human cycle and stuff for like 95% and then read the word organisms too late with like 5 minutes to go so I just stuck in antibiotics and mutation. I thought it was nicely separated but the more I read over it the more I think I've made such a stupid mistake..
    I swear it was just humans though, it repeated it twice within the question. Other organisms were just associated with the "development" part of the question - was my understanding...?
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    (Original post by ps1265A)
    Sure not ATPsynthase?


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    Definitely note, ATPsynthase makes ATP, ATP is not made in the cross bridge cycle
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    Okay im not a high achieving biology student lol,so for the essay I did 10)a) and I wrote:
    1)Temperature Control
    2)Kinesis and Taxis
    3)Arc Reflex
    4)Sympathetic and Parasympathetic Nervous System
    5)Adaptations and how they can survive (very brief)

    How many marks would I get?:banana::banana:
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    (Original post by Fuenciado)
    Can't you still get like most of the marks for the question though and in the worse case you'll lose 3 marks for relevance?
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    The thing is I dont think you can get awarded any marks if it doesnt even relate to the question I think I answered it totally different to how they wanted it
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    (Original post by georgiariane)
    I swear it was just humans though, it repeated it twice within the question. Other organisms were just associated with the "development" part of the question - was my understanding...?
    For B I wrote about:
    Oestrous cycle
    Oestrogen as a transcription factor
    Protooncogenes and tumour suppressors
    Stem cells
    Intensive farming
    Mitosis

    I pretty sure these all answer the question, "the importance to humans of the control of growth, development and reproduction in organisms, including themselves"
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    I didn't mention tropisms and kinesis for the essay but got everything else, will it cost me marks?
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    (Original post by georgiariane)
    I swear it was just humans though, it repeated it twice within the question. Other organisms were just associated with the "development" part of the question - was my understanding...?
    I know I really thought that too but I doubted myself at the end and also I know a lot of people that spoke about mostly ecology stuff for that question, which Im still confused about. Arhhhh I don't know Obviously I want it to be right.
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    that was hard and i am sad
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    About the ratio question, If my memory didn't deceive me, it was the ratio of Experiment 2 (top curve) : Experiment 3 (lowest curve)

    and the figures I got from extrapolating from the curves were 114 : 48 (dividing both by 48) the simplest ration is 2.37:1

    I thought you can leave it as i is or round it to 2.4 : 1 , either way there should be a range, since the Y axis was a bit hard to read accurately ....
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    I know I will have lost marks on graph/how science works questions as always, and there are other questions I thought I answered really well but will have lost marks for not using some specific words etc. as is typical for biology, but still feeling quite confident. Pls note this is not an unofficial mark scheme lol I'm just saying what I got and there were some things I guessed

    These were my answers as far as I can remember...

    1. a) Actin connects to the Z-line; myosin ATPase hydrolyses ATP, I put the myosin part in just in case but don't think necessary; tropomyosin binds to actin etc
    b) Oh dear. For the myosin mutation thing I said something along the lines of myosin molecules couldn't bind to each other so the power stroke wouldn't work because the filaments wouldn't be able to move relative to each other :|

    2. a) LH stimulates release of eggs from ovaries (in hindsight I might have accidentally said into the ovaries, if so ****) and stimulates secretion of progesterone from corpus luteum
    b) The testosterone one - so it would inhibit secretion of GnRH so pituitary gland no longer stimulated to secrete FSH and LH, so testes no longer stimulated to secrete testosterone, so testosterone levels in the blood fall, then topped it off with "this is an example of negative feedback" lmao
    c) Pretty much wrote the same thing but said testes would no longer be stimulated to produce sperm cells

    3. I can't really remember the order of the questions, was this the Pacinian corpuscle one?
    a) Mechanical pressure causes membrane of sensory neurone to stretch, sodium ion channels open and sodium ions diffuse into the sensory neurone, making membrane potential less negative. At the end I said something about the layers of connective tissue with viscous gel between just in case haha.
    b) Suggest one reason why MS sufferers have less muscle control blah blah, I said less myelin sheath and nerve impulse travels more slowly along unmyelinated axons so slower/delayed muscle contraction
    c) It was a hydrophobic molecule so it would pass through the membrane by simple diffusion
    d) Why do cannabinoids prevent muscle contraction... calcium ions do not diffuse into synaptic knob so do not bind to receptors on synaptic vesicles which do not fuse with presynaptic membrane so acetylcholine does not diffuse across synaptic cleft and bind to receptors on postsynaptic membrane blah blah blah...
    e) Um lol, for the cannabis one I said it would still have its effect on NMJs but since it didn't enter brain tissue it wouldn't have harmful side effects/damage brain tissue/wouldn't prevent synaptic transmission in the brain

    4. I really can't remember the question order so I'm going to say this was the smoking one.
    a) Questionnaire Q - I said the people who responded to the questionnaire might not be representative of the population and also that kids might lie because they could be ashamed to say that their parents smoke (no offence to anyone whose parents smoke lmao)
    b) Support the conclusion, blah blah less expression of that gene and it was significant because SE did not overlap, expression of gene reduced the risk of allergic reactions so those children whose parents smoked would be more susceptible (basically just repeated stem of the question...)
    c) DNA methylation, I said RNA polymerase would be less able to bind to promoter region of the gene so less mRNA produced so less translation and therefore less of the encoded polypeptide produced

    5. a) tumour suppressor gene? umm think I said it regulates cell division so if it was mutated and became inactive cells would divide uncontrollably
    b) not all mutations change the AA sequence because genetic code degenerate/more than one codon encodes the same amino acid so a substitution mutation could be silent (it was only one mark though)
    c) The monoclonal antibodies :|.. I said antibodies complementary to the growth factor receptors on cancer cells so would bind to them and prevent growth factors from binding so the cancer cells wold no longer be stimulated to divide

    6. I can't remember what part a) was. For the ratio in part b) I put 118:53, based on the June 11 MS I think 118:53, 2.2(7):1 or 1:0.44 (ish - graph reading was subjective) would all get two marks, and if you flipped them round you would get one mark.
    c) Oh Jesus I wrote loads for this one about the sympathetic and parasympathetic..
    I said it showed that they were both involved in the response: all three curves showed decrease in heart rate with increasing blood pressure; heart rate was lower when SNS inhibited (so SNS involved); heart rate higher when PNS inhibited (so PNS involved); PNS had a more important role than SNS because there was bigger difference blah blah

    7. I think this was the tropisms one?
    a) Similarity is that they are both directional responses to external stimuli, for a difference I just said taxes are in animals and tropisms are in plants
    b) Urgh so you had to describe what the pictures showed you for three marks -.-
    I just said the first one showed gravity made the roots grow downwards, the second one showed they grew away from the salt, and for a third mark I said maybe it showed that the response to salt outweighed the response to gravity??
    c) This IAA one took me a while ... on the salt-exposed side there were more carrier proteins so more IAA transported out so lower concentration of IAA on that side, therefore the cells elongated more than the other side and the root tip bent away from the salt

    8. a) Why were the able to maintain glucose concentration after not eating for 48 hours? Because pancreas detects drop in blood glucose, alpha cells of islets of Langerhans secrete glucagon which binds to receptors on liver cells and activates glycogenolysis and gluconeogenesis
    b) Suggest how mutant mice maintained a constant glucose concentration compared to the normal mice or something..
    I said that because the liver wasn't responding to glucagon, eventually blood glucose got very low and glucagon got very high and instead bound to receptors on intestines and kidneys, activating the PKC1 gene or whatever it was, and that enzyme made glucose. This wouldn't happen in the normal mice because glucagon levels don't get high enough for that gene to be stimulated?
    c) The mean expression of the gene was significantly higher in the mutant mice both in kidneys and intestines; probability that difference is due to chance is less than 1%

    9. a) Same restriction enzymes so they would cut at the same recognition sites producing analogous fragments/any difference in fragment size would be due to the different alleles?
    b) Primers have complementary sequence to the specific fragment to which they bind - they only form hydrogen bonds/complementary base pairs with this fragment
    c) "Use all the information given to explain the results", I was a little worried because it gave the lengths of the two primers used so I felt like I had to use that, yet since they were only the primers and not the whole allele, I didn't feel it was actually possible to identify which one was L and N? So I answered quite vaguely, along the lines of:
    L and N/parents both homozygous, one has two copies of r allele, one has two copies of R, so only one and seen, and the alleles are different lengths so they move different distances;
    All the offspring were heterozygous so they had one r and one R, so they had two bands which were half as thick?

    d) Why were the control group used? Umm I said to see the effect of insecticide in the absence of any resistance allele
    e) "PM activity is involved in resistance but there are other factors too explain how graph supports this conclusion", thought this was a nice end to the question...yeah in the resistance group with PM inhibited, more of them died than the ones without PM inhibited, so PM must play a role in the resistance; but fewer of them died than the non-resistant flies which couldn't have been due to PM so another factor must play a role in the resistance.

    10 a) I wrote:
    Temperature - too cold, lowers rate of enzyme catalysed reactions; too hot, enzymes denature;
    when mammals are too cold they shiver, shunt vessels dilate, brown fat heat production by uncoupling proteins (off spec); when too hot they sweat;
    Blood glucose concentration - I explained this in terms of water potential? e.g. blood glucose too low, water potential of blood would increase, water enters cells by osmosis which then burst?
    when too low - glucagon, when too high - insulin, brief discussion of all the massive G words
    Feedback inhibition of metabolic pathways (off spec) - important because carrying on with a pathway when there's already plenty of the product is energetically wasteful. I was going to talk about glycolysis with PFK but for some reason wrote about PanK in CoA biosynthesis instead, I'd been reading about it recently haha
    Transpiration - plants close their stomata when it's hot/dry/windy to prevent excessive water loss (needed for photosynthesis, cell turgor etc), then I also talked about the importance of reopening stomata again when environmental conditions changed in terms of photorespiration (off spec)
    Tropisms - just talked about IAA and positive phototropism
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    (Original post by sofja26)
    I know I really thought that too but I doubted myself at the end and also I know a lot of people that spoke about mostly ecology stuff for that question, which Im still confused about. Arhhhh I don't know Obviously I want it to be right.
    If I'm honest I don't see how a lot of the ecology stuff that sine people wrote about is related to the question at all
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    For essay B, I wrote about
    Mitosis cancer
    intensive farming and crop
    control of disease and immune response(as bacteria and virus are organisms as well)
    control of birth rate
    are these relevant?
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    Name:  AAAAAAA.jpg
Views: 686
Size:  176.9 KB

    It's marked like the above picture says.

    QWC - out of 3
    Breadth - out of 3
    Relevance - out of 3

    Then content is out of 16, with 14 marks for: "Some AS/A2 content in four topics and good content in three topics." Then 16 can either be for 12 in content and 2 above and beyond (which would have to be pretty complex) or 14 for content and above and beyond in one topic. But it's marked in a very specific way. Rambling will lose relevance marks but not including a range of topics loses breadth marks.
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    (Original post by ghost_rebel)
    Okay im not a high achieving biology student lol,so for the essay I did 10)a) and I wrote:
    1)Temperature Control
    2)Kinesis and Taxis
    3)Arc Reflex
    4)Sympathetic and Parasympathetic Nervous System
    5)Adaptations and how they can survive (very brief)

    How many marks would I get?:banana::banana:
    One does not simply say how many marks you got from that, the essay was about the "IMPORTANCE" so it's vital to link all the topics you talk about to it ....
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    pretty sure it's not ATPase it's water..
    but either way they might allow both, it was quite ambiguous
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    (Original post by lauraedgar)
    If I'm honest I don't see how a lot of the ecology stuff that sine people wrote about is related to the question at all
    I didnt I just got more confused, I just hope that Im over thinking this exam and that its gone better than I thought it has
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    (Original post by lauraedgar)
    For B I wrote about:
    Oestrous cycle
    Oestrogen as a transcription factor
    Protooncogenes and tumour suppressors
    Stem cells
    Intensive farming
    Mitosis

    I pretty sure these all answer the question, "the importance to humans of the control of growth, development and reproduction in organisms, including themselves"
    How is the oestrogen cycle relivent to the question? Sorry for being dim, I think there are two ways of interpreting it
    1) humans (within their own functioning)
    2) how other organisms benefit humans
 
 
 
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