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    (Original post by racheatworld)
    Yes! Like you, I also put simple diffusion/osmosis because although they are polar, water molecules are small. Also like you I didn't get the second mark (I was never even taught that there was a chance water molecules could hit the hydrophilic -you said hydrophobic but I assume you mean hydrophillic, phosphate group heads).

    Some of my friends came out of the exam having put the symplast/apoplast pathways but it deliberately said cell surface membrane. Cell surface membranes can be both in animal or plant cells, so for one reason why would the answer be the pathways that are only present in plant cells?
    Its definitely a grey area. I've made my argument, other people will contradict it, as they should, because its a grey area. However, apart from my argument, I don't see any other possible answer for the second mark, so I think its a case of 'better than nothing' in choosing my/my teacher's answer. I could definitely be wrong. It is only one mark in the end, and there's a good chance, that you may just get two marks for an expanded definition of osmosis/diffusion for example.
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    (Original post by liam532)
    can you also put flexible shape (for phagocytosis engulfment) for the neutrophil one?

    also, what was the answer to the stem one? I put some thing like the distance for the water to travel to the cells which need it for photosynthesis is now shorter, so it is more likely to have the required energy to survive longer; does this make sense? was kinda guessing lol
    I guessed on the cutting stem question too. I just put the Xylem is now more exposed to the water so water moves up by capillarity. This enables cells to live longer as water is used for photosynthesis.
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    (Original post by racheatworld)
    I wasn't talking about the onion epidermis cell question. I was talking about the question "how does water move through the cell surface membrane", nothing was mentioned about cell types here.
    the question: what routes do water molecules take across the cell surface membrane
    which was within a question about onion epidermis cells.
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    (Original post by adilh301)
    the question: what routes do water molecules take across the cell surface membrane
    which was within a question about onion epidermis cells.
    It wasn't, was it? Even if it was, it didn't directly mention what rout does water take accross onion epidermis cell membranes. Therefore I assume that it can be any cell membrane.
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    (Original post by adilh301)
    the question you had to answer was in the specification you just had to use your knowledge to apply it.
    -Cell signalling for the first one
    - something related to tissue fluid/water potential for the second one.
    a really easy paper just really varied answers across the paper.
    Ahh okay, I wasn't really expecting this type of question.
    We shall see what are results are in march, fingers crossed!
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    (Original post by adilh301)
    hmm k leave it at that and i let the fact that u called the heads hydrophobic because i assumed it was a typo on your part im sure everyone knows that the heads are water loving.
    I've revised wrongly then. Don't try and patronise me 'everyone knows that'.
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    (Original post by Rassam)
    Yes but it was clearly labelling one of bronchi, making it a bronchus.
    No, let's settle this, it was definitely a bronchiole, the order goes:
    Trachea
    Bronchi
    Bronchioles
    Alveoli

    http://en.wikipedia.org/wiki/Bronchiole
    http://en.wikipedia.org/wiki/Bronchus
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    (Original post by racheatworld)
    It wasn't, was it? Even if it was, it didn't directly mention what rout does water take accross onion epidermis cell membranes. Therefore I assume that it can be any cell membrane.
    yes,yes it was that my friend isn't a grey area. The question was a subquestion in the question about onion epidermis cells. it didnt directly ask whate route it took across onion epidermis membranes but it did ask for routeS implying you need to mention one pathway nyway no need to get all stressed out over 2 marks one will be wrong one will be correct it will never be down to both being correct it will always say R: one of them.
    none of us are examiners so none of us can say any of the possibilities in such a grey area are wrong.
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    (Original post by thesalamander123)


    No, let's settle this, it was definitely a bronchiole, the order goes:
    Trachea
    Bronchi
    Bronchioles
    Alveoli

    http://en.wikipedia.org/wiki/Bronchiole
    http://en.wikipedia.org/wiki/Bronchus
    I thought it was a Bronchus. It was pointing to the one, thick bronchus. You could see the alveoli were attached to the bronchioles which came off the bronchus and the arrow was no-where near the smaller branches.
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    (Original post by racheatworld)
    It wasn't, was it? Even if it was, it didn't directly mention what rout does water take accross onion epidermis cell membranes. Therefore I assume that it can be any cell membrane.
    Yep, you're right, it said 'cell surface membranes'.

    The wording of these questions is also a pain in the ****ing arse, its really annoying (as pains in your arse tend to be...)
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    (Original post by racheatworld)
    For the question about "What ultrastructure of the Neutrophils enables it to carry out their function" I was reluctant to put lobed nucleus although I knew it was right, because I'm sure a nucleus doesn't count as "ultrastructure" because it can be seen in a light microscope as well as an electron microscope. I wrote instead about lysosomes, many vesicles and complex cytoskeleton (actin filaments to move the vesicles containing foreign material to lysosomes to be digested by hydrolitic enzymes). Is it right to say a nucleus isn't ultrastructure?
    Never learnt the word ultrastructure, or if we had, I hadn't remembered it.
    I just wrote down everything I knew about Neutrophils.
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    (Original post by thesalamander123)


    No, let's settle this, it was definitely a bronchiole, the order goes:
    Trachea
    Bronchi
    Bronchioles
    Alveoli

    http://en.wikipedia.org/wiki/Bronchiole
    http://en.wikipedia.org/wiki/Bronchus
    biggest grey area of them all even the book contradicts itself here
    figure 1 page 46: bronchioles are shown to be only the parts that hold the alveoli the bit they branch off from is labelled as the bronchi
    page 48:
    the bronchioles are much narrower than the bronchioles. the larger bronchioles may have some cartillage
    so the structure labelled could have been a bronchiole with cartillage.

    there werent many grey areas in this paper and the two grey areas everyones debating about are worth 1+2 marks- hardly worth the effort when you could be revising for your next exam.
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    (Original post by adilh301)
    yes,yes it was that my friend isn't a grey area. The question was a subquestion in the question about onion epidermis cells. it didnt directly ask whate route it took across onion epidermis membranes but it did ask for routeS implying you need to mention one pathway nyway no need to get all stressed out over 2 marks one will be wrong one will be correct it will never be down to both being correct it will always say R: one of them.
    none of us are examiners so none of us can say any of the possibilities in such a grey area are wrong.
    I know OCR don't tend to be the best at wording questions, but they would definitely not just put "cell surface membranes" and just because it is within a question about onion epidermal cells expect you to read their minds and assume that they are talking about plant cells? They would word it clearer than that, I'm sure they would put something at the very least "explain how water moves across these cell membranes" which would then lead you to look back and see they were talking about the onion cells. Don't worry, I'm not stressed, I'm just sure I read the question as "cell surface membranes"
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    (Original post by DonFahad)
    Yep, you're right, it said 'cell surface membranes'.

    The wording of these questions is also a pain in the ****ing arse, its really annoying (as pains in your arse tend to be...)
    hahahahahaah pain in the arse
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    (Original post by DonFahad)
    I've revised wrongly then. Don't try and patronise me 'everyone knows that'.
    wasnt patronising you you just made a typo.
    Hydrophobic tail is water hating
    Hydrophillic head is water loving
    you said hydrophobic head, so either you made a typo or yeah youve been revising wrong.
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    (Original post by adilh301)
    wasnt patronising you you just made a typo.
    Hydrophobic tail is water hating
    Hydrophillic head is water loving
    you said hydrophobic head, so either you made a typo or yeah youve been revising wrong.
    I've been revising wrong. Or I've just got them muddled up again.... Irritating.
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    (Original post by DonFahad)
    Its not in the spec or the book, but bear in mind, that they ask you to apply your knowledge to situations you haven't been in before, and with the knowledge that water molecules are very small and slightly polar, you could have applied that to the 'cell surface membrane', as worded in the question, which has hydrophobic phosphate ends. Im sure I didnt mishear her, she, in fact, said that the apoplast/symplast route was wrong, and irrelevant, although as you said, there is a small chance she herself could be wrong (I really doubt it, I've told you her credentials. She got one of our students to 3rd in the Biology Olympiad last year). Hydrophobic is repelling water, I'm sure? phobia = fear, phyllic = phallus = love?

    Again, its a grey area. What I can say is, we can have a bet, in the form that, when the markscheme comes out, and I am right, you can rep me, and if you are right, I'll rep you
    the lipid tails are hydrophobic the phosphate heads are hydrophillic.
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    (Original post by Sohailahmed)
    hahahahahaah pain in the arse
    Sohail man, are you Pakistani? We've got a society man, TSR Pakistani Society look it up yeah?

    Also, yeh. Pains in the arse FTL
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    (Original post by adilh301)
    the lipid tails are hydrophobic the phosphate heads are hydrophillic.
    yes thank you for pointing that out again, very nice of you. You're only the 4th person to tell me. tyvm.
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    (Original post by DonFahad)
    yes thank you for pointing that out again, very nice of you. You're only the 4th person to tell me. tyvm.
    considering that could be used to deconstruct your whole phosphate head deflecting water molecules argument id say its worth it but yeah ill leave this 2 mark grey area be now :P.
 
 
 
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