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    What are histones? Does anyone have a pic please?

    The hydrophobic tails in the phospholipid bilayer allows water to pass through but isn't water polar as it has a dipole?

    Thanks
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    (Original post by the_wizzz)
    What are histones? Does anyone have a pic please?

    The hydrophobic tails in the phospholipid bilayer allows water to pass through but isn't water polar as it has a dipole?

    Thanks
    Yeah water is polar. So hydrphobic (water hating) tails do not allow polar molecules through, however water molecules are small enough to diffuse through by osmosis.
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    Histones are proteins associated with chromosomes
    Most polar molecules are not soluble in the phospholipid bilayer, but water is very small.
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    So water just passes through the bilayer cos its small even though it is polar and fatty acid tails are insolbule in it?

    Can histones be seen or are they just constituents?
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    (Original post by the_wizzz)
    So water just passes through the bilayer cos its small even though it is polar and fatty acid tails are insolbule in it?
    yes, it diffuses by osmosis down its water potential gradient. also, large polar moleculs and ions need protein channels or carrier proteins through which facilitated diffusion occurs
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    (Original post by the_wizzz)
    So water just passes through the bilayer cos its small even though it is polar and fatty acid tails are insolbule in it?

    Can histones be seen or are they just constituents?
    Histones can be seen on high-res electron microscopy. DNA coils around them when not replicating/being transcribed - it is all part of the superstructure of DNA that enables it to be compacted. They consist of 8 subunits (I think) and are highly basic.
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    (Original post by the_wizzz)
    What are histones? Does anyone have a pic please?

    The hydrophobic tails in the phospholipid bilayer allows water to pass through but isn't water polar as it has a dipole?

    Thanks
    If you're looking for pictures of Histones:
    http://images.google.co.uk/images?q=...O-8859-1&hl=en
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    (Original post by jamal1425)
    If you're looking for pictures of Histones:
    http://images.google.co.uk/images?q=...O-8859-1&hl=en
    Ooooh, pretty!
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    (Original post by jamal1425)
    If you're looking for pictures of Histones:
    http://images.google.co.uk/images?q=...O-8859-1&hl=en

    They all look different
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    (Original post by the_wizzz)
    What are histones? Does anyone have a pic please?

    The hydrophobic tails in the phospholipid bilayer allows water to pass through but isn't water polar as it has a dipole?

    Thanks
    as far as i know,you dont need to know the structure of histones as they are basically very very small...all you have to know is that it looks like a needle and the DNA coils around it during cell division...
    what is it for??i think its for reducing the area needed to store the replicated DNA.....to make the total DNA amount compact..


    and as for water....bear in mind that small molecules diffuse through..but larger molecules like ammonia does not...
 
 
 
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