Hey there! Sign in to join this conversationNew here? Join for free
    Offline

    0
    ReputationRep:
    (Original post by Flint_09)
    hope higher than for u
    a question, why can't the first shell hold more than two electrons?
    Cause it has only 1 orbital?
    Offline

    0
    ReputationRep:
    what did u gyz put for da one about the smoke traveling through the xylem in the wood???
    Offline

    7
    ReputationRep:
    (Original post by TattyBoJangles)
    Let's hope bronchus is right then xD

    For that water thing - I'm pretty sure the question was, "How does water move across the cell surface membrane?"
    Surely symplast and vacuolar are describing what the water does once it's passed through the plasma membrane, not describing how water actually enters the cell in the first place?
    I put that water on its own is small enough to pass through the bilayer via osmosis, but if there are solutes / larger molecules with it, then channel proteins may have to facilitate the diffusion.?
    this is what I thought Vacuolar and symplast surely relate to the movement of water through the cell and not the membrane
    Offline

    19
    ReputationRep:
    (Original post by adilh301)
    yeah i thought that at first aswell but if you have the OCR text book on page 73 that pretty much looks like their question and the answer theyd answer.
    Same book, page 22/23.

    Confusion.


    Edit: 26/27, sorry.
    Offline

    2
    ReputationRep:
    (Original post by Flint_09)
    hope u get higher than that lol
    a question, why can't the first shell hold more than two electrons?
    because they are ****ed up lol!
    Offline

    7
    ReputationRep:
    also this seems to suggest that the answer to the bronchus/ bronchiole debate is bronchiole...

    I may be wrong but the labelled bit in the exam looks like the lobular bronchiole to me

    http://www.google.co.uk/imgres?imgur...t:429,r:10,s:0
    Offline

    0
    ReputationRep:
    (Original post by Rassam)
    Cause it has only 1 orbital?
    2nsquared formula
    the 1st shell is 2*1(squared) = 2 thats the formula answer
    but yeah explanation is it only has 1 subshell which is the 1s orbital which is also only capable of containing 2 electrons but dont think theyd ask for it in that much detail. im worried about those mole questions with 10 tonnes of a substance >.<.
    Offline

    0
    ReputationRep:
    (Original post by jaez121)
    because they are ****ed up lol!
    spot on!
    Offline

    2
    ReputationRep:
    (Original post by msimon)
    what did u gyz put for da one about the smoke travel through the wood??
    God that was such a weird question. I had no idea what to put. I think something about it being able to travel through the xylem uninterrupted because it was a long tube or something. I think I've got that one wrong.
    Offline

    7
    ReputationRep:
    (Original post by giraffegiraffe)
    I think i put something like that too .. and for the one before about histamine making the muscle contract or something, that was to do with cell receptor molecules / target cells etc right? the questions were a bit strange, hard to know what they wanted from us.



    i put symplast etc for that one too.. quite a few people did i think but a lot of people but about cell membrane bilayer channel proteins etc! maybe they'll except both because the question could be either? (or lets hope so...)
    oh gosh most of the questions were way too vague! or those "suggest..." questions .... where was all the "meaty" stuff on the heart, lungs, translocation, haemoglobin, lymph, cardiac cycle ... etc that we spent soo long revising!!? i think the "suggest" questions and the ambiguity on this paper made it harder than a lot of the past papers we've done
    yeah man I think the histamine question was asking about receptor mediated endocytosis... taking in the histamine into the cell and causing the smooth muscle to contract
    Offline

    0
    ReputationRep:
    (Original post by TattyBoJangles)
    Same book, page 22/23.

    Confusion.


    Edit: 26/27, sorry.
    26/27 refers to osmosis the question asked the routes water molecules take to cross the cell surface membrane
    quote page 73:
    How does water move between cells?
    When plant cells are touching each other,water molecules can pass frome one cell to another.......etc etc.
    What ROUTE can water take between cells?
    the apoplast pathway
    the symplast pathway
    the vacuolar pathway
    info on p 26/27 would be more relevant if osmosis was used in the question or if osmosis was explained as a route somewhere on p26/27.
    Offline

    0
    ReputationRep:
    (Original post by adilh301)
    2nsquared formula
    the 1st shell is 2*1(squared) = 2 thats the formula answer
    but yeah explanation is it only has 1 subshell which is the 1s orbital which is also only capable of containing 2 electrons but dont think theyd ask for it in that much detail. im worried about those mole questions with 10 tonnes of a substance >.<.
    yup
    Offline

    0
    ReputationRep:
    (Original post by Tabers)
    God that was such a weird question. I had no idea what to put. I think something about it being able to travel through the xylem uninterrupted because it was a long tube or something. I think I've got that one wrong.
    lol... i put sumthing abt pits and since it said steam.. i said through the xylem by capillary action
    Offline

    2
    ReputationRep:
    lets clear this up... water enters the plasma membrane by diffusing straight throught the phospholipid bilayer by osmosis and through channel proteins by facillitated diffusion. no answers involved apoplast symplast etc
    Offline

    19
    ReputationRep:
    (Original post by adilh301)
    26/27 refers to osmosis the question asked the routes water molecules take to cross the cell surface membrane
    quote page 73:

    info on p 26/27 would be more relevant if osmosis was used in the question or if osmosis was explained as a route somewhere on p26/27.
    I can't remember the question exactly, but the symplast and vacuolar pathways don't describe how water enters cells through the cell surface membrane initially. That just describes the route water takes once it has already passed through the bilayer.
    Offline

    0
    ReputationRep:
    Say for the adaptations of neutrophils question, I mentioned 3 things. But if 2 are correct and 1 wrong, will I lose marks?

    Also, bronchus or bronchioles?

    Accuracy of experiment? I said length of time in solution needs to be the same.
    Offline

    0
    ReputationRep:
    (Original post by msimon)
    lol... i put sumthing abt pits and since it said steam.. i said through the xylem by capillary action
    i put xylem is lignified thus waterproofed/cell contents die(dont knw if that bits necessary) so the steam can travel through the xylem vessel without being absorbed by the vessel as the steam would be water molecules? and i didnt think abt capillary action steams lighter than air so doesn't it always go up? >.<
    Offline

    2
    ReputationRep:
    (Original post by Flint_09)
    spot on!
    lol! i m gona say tht to the examiner
    Offline

    0
    ReputationRep:
    what did u gyz put for da one for 5 marks???
    Offline

    0
    ReputationRep:
    (Original post by kimmey)
    lets clear this up... water enters the plasma membrane by diffusing straight throught the phospholipid bilayer by osmosis and through channel proteins by facillitated diffusion. no answers involved apoplast symplast etc
    ru sure? looking at the threads alot of people put symplast and vacuolar pathways, but not apoplast which is another pathway because it lets water pass between cells.
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Did TEF Bronze Award affect your UCAS choices?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Quick reply
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.