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    (Original post by Marshymallow)
    Attachment 222400 i put an X in the far left hand box, but the mark scheme says it should be in the far right? Can anyone explain why? :/


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    Because the bacteria would be in the far left as it's the most distant relative out of the three domains. The Eukaryotes are in the far right because they are more closely related to the Archaea (in the middle). This can be seen with the junctions on the diagram, which represent a common ancestor. Hope this helped!
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    (Original post by vishalb)
    what kind of things would we need to know about plant fibres sustainability?
    Well someone uploaded notes onto this thread and it included this:

    Sustainability
    • (NOT A MARK - Oil-based plastics and fuels are not sustainable as):
    • Release carbon dioxide / ref. to global warming / pollution ;
    • plastic is from oil ;
    • oil is a non-renewable resource ;
    • Generation of non-biodegradable waste ;
    • (however) {plants / starch} are renewable ;
    • plants can be re-grown / eq ;
    • (fibres often biodegradable so) doesn’t accumulate / doesn’t take up landfill space / eq ;


    Disadvantages
    • The ropes made from plant fibres aren’t as strong;
    • Bags made out of paper are less strong than plastic bags and disintegrate when wet;
    • Degradation of waste requires aerobic organisms, so little happens in deep landfill sites;
    • Closer to the surface, methane (a greenhouse gas) is often produced;
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    (Original post by Ambar)
    Because the bacteria would be in the far left as it's the most distant relative out of the three domains. The Eukaryotes are in the far right because they are more closely related to the Archaea (in the middle). This can be seen with the junctions on the diagram, which represent a common ancestor. Hope this helped!
    Thank you, i still don't understand why bacteria is the most distantly related? Surely bacteria and archaea are most closely related ... This table was earlier on in the question and Q is eukaryotic, and it has the least things in common with the other two, so shouldn't it be the most distantly related? Name:  ImageUploadedByStudent Room1370192079.658574.jpg
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    (Original post by Marshymallow)
    Thank you, i still don't understand why bacteria is the most distantly related? Surely bacteria and archaea are most closely related ... This table was earlier on in the question and Q is eukaryotic, and it has the least things in common with the other two, so shouldn't it be the most distantly related? Name:  ImageUploadedByStudent Room1370192079.658574.jpg
Views: 199
Size:  122.1 KB


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    Q and R are most distantly related..

    P and Q have 1 thing in common
    P and R have 3 things in common
    Q and R have nothing in common
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    (Original post by gold_)
    uses of mitosis:

    - growth of multicellular organisms
    - repair damaged tissue
    edit: Asexual reproduction...lol hope i don't forget like that in the exam

    cell cycle:

    Interphase: Cell doubles dna content, increase in atp and organelles replicated.

    Mitosis: 4 stages p.m.a.t.

    -prophase: 1)chromosomes shorten and thicken 2) centrioles move to opposite ends and forms spindle 3) nuclear envelope breaks down.

    -metaphase: 1)chromosomes line up in the middle 3)there centromere attach to the spindle

    -anaphase: 1)spindle contracts seperating each sister chromatid to opposite ends pulling the centromere first 2) spindle breaks down

    -telophase: 1)chromosomes unravel 2)nuclear envelope forms around both sets of chromosomes 3) nucleolus forms 4) cytoplasm divides forming two cells genetically identical.
    thankyou :d
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    (Original post by Marshymallow)
    Thank you, i still don't understand why bacteria is the most distantly related? Surely bacteria and archaea are most closely related ... This table was earlier on in the question and Q is eukaryotic, and it has the least things in common with the other two, so shouldn't it be the most distantly related? Name:  ImageUploadedByStudent Room1370192079.658574.jpg
Views: 199
Size:  122.1 KB


    Posted from TSR Mobile

    Also, if you remember Woese's diagram, Archaea and Eukaryotes are more closely related than bacteria. Again, if you remember the diagram, the junctions show the common ancestor. Bacteria only has one common ancestor with the other two, whereas archaea and Eukaryotes share two common ancestors.
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    (Original post by mynameisntbobk)
    Q and R are most distantly related..

    P and Q have 1 thing in common
    P and R have 3 things in common
    Q and R have nothing in common
    This is true, but then because P and R have 3 things in common, why aren't they the ones closer together, with R being at the far right and Q being the far left because they have nothing in common?

    Eh nonetheless, all the diagrams show Archaea and Eukarya closer together than with Bacteria, so we just have to remember that :P
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    what do we have know about E colia and galactosidase , I can't find it in the revision guide and I have a feeling it will turn up tomorrow
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    (Original post by mynameisntbobk)
    Q and R are most distantly related..

    P and Q have 1 thing in common
    P and R have 3 things in common
    Q and R have nothing in common
    Yes i understand that Q and R are most distantly related. I don't understand how P and Q (archaea and eukaryotes) are most closely related, i would have thought P and R (archaea and bacteria) would be: as you said they have 3 things in common... But according to the answer to the tree question eukaryotes are most closely related to archaea?


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    (Original post by The Assassin)
    This is true, but then because P and R have 3 things in common, why aren't they the ones closer together, with R being at the far right and Q being the far left because they have nothing in common?

    Eh nonetheless, all the diagrams show Archaea and Eukarya closer together than with Bacteria, so we just have to remember that :P
    (Original post by Marshymallow)
    Yes i understand that Q and R are most distantly related. I don't understand how P and Q (archaea and eukaryotes) are most closely related, i would have thought P and R (archaea and bacteria) would be: as you said they have 3 things in common... But according to the answer to the tree question eukaryotes are most closely related to archaea?


    Posted from TSR Mobile

    oh right you're talking about the second part of the question. yeah I thought that was weird as well, I think there may be other molecular factors that make Eukarya closely related to Archaea than they give in the question maybe

    Yep, I got that question wrong twice because I used the information in the question, not again
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    anyone please teeelll me...do we have to study meiosis steps ....like sperogenesis???????????
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    (Original post by Ambar)
    Also, if you remember Woese's diagram, Archaea and Eukaryotes are more closely related than bacteria. Again, if you remember the diagram, the junctions show the common ancestor. Bacteria only has one common ancestor with the other two, whereas archaea and Eukaryotes share two common ancestors.
    Ahhh okay, i don't ever remember learning woese's diagram :// oh well, i'll remember that for tomorrow! Thanks!


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    (Original post by Daniel Atieh)
    anyone please teeelll me...do we have to study meiosis steps ....like sperogenesis???????????
    No, you just have to know that it produces genetically diverse gametes (Crossing Over and Independent Assortment).
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    Can someone tell me experiment of root tip in point form? Thankyou
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    (Original post by vishalb)
    yes please!
    June 2009 paper and markscheme
    Attached Images
  1. File Type: pdf Unit 2 Jun 2009 question paper.pdf (682.9 KB, 33 views)
  2. File Type: pdf Unit 2 June 2009 markscheme (1).pdf (563.9 KB, 28 views)
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    What are stalked particles?
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    (Original post by The Assassin)
    This is true, but then because P and R have 3 things in common, why aren't they the ones closer together, with R being at the far right and Q being the far left because they have nothing in common?

    Eh nonetheless, all the diagrams show Archaea and Eukarya closer together than with Bacteria, so we just have to remember that :P
    is this sentence correct? " Genetic variation allows individuals in a species to adapt better and survive in a changing environment? or i shud say in their environment? Thanks!
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    reallly nervous now (

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    Hi, i was wondering which experiment you guys think is going to come up
    Thanksss
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    so any questions anyone's adamant will come up? and any guess' on the core pracs?
 
 
 
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