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Official AQA Biology Unit 3 14th May 2013 NEW SPEC Watch

  • View Poll Results: VOTE HERE--> What do you think the 6 marker will be?
    Explaining features/functions of the lungs
    8.15%
    Ventilation
    11.11%
    Blood flow in heart
    16.30%
    Explain Transport in blood
    5.19%
    Explain Transport in plants
    5.19%
    Evaluate kidney transplants/dialysis
    28.89%
    Explain biogas generator
    31.11%
    Other (please comment with your suggestion)
    12.59%
    The effects of global warming
    8.15%
    Evaluate the use of Artificial blood
    13.33%
    Evaluate the effectiveness of sports drinks
    11.11%

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    I think it links with this bit;
    "land, with toxic chemicals such as pesticides and
    herbicides, which may be washed from the land
    into waterways."
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    how is the villi adapted to exchange food into the blood?
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    (Original post by C-king)
    how is the villi adapted to exchange food into the blood?
    -Thin Walls
    - Microlvilli which give it a large surface area
    - Good blood supply from the capillaries maintains the concentration gradient and assists quick absorption
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    (Original post by C-king)
    how is the villi adapted to exchange food into the blood?
    Villi, folded many times and have micro villi, this drastically increases the surface area.
    Have a rich blood supply, to maintain a concentration gradient
    They are one cell thick shorter diffusion path.
    Have lots of mitochondria to release energy for active transport.
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    Each villus has many microvilli on its surface to vastly increase surface are for diffusion. Each villus contains a capillary which provides a rich blood supply and therefore a constant gradient for diffusion to occur. The lining of each villus is thin to minimize the distance for diffusion to occur.
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    (Original post by sneakbo2)
    -Thin Walls
    - Microlvilli which give it a large surface area
    - Good blood supply from the capillaries maintains the concentration gradient and assists quick absorption
    Also it can move molecules into blood by active transport and diffusion, meaning food molecule snever diffuse out of blood or are wasted in faeces
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    What are the environmental effects of building dams to supply water?
    Not sure if its in the spec but its in the Nelson Thorns book
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    Why do farmers farm Herbivores as opposed to carnivores? (2 marks) - This is a past paper question that has come up many times so I think it's useful to learn
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    B2

    what does recessive and dominant allele mean?
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    (Original post by sneakbo2)
    Why do farmers farm Herbivores as opposed to carnivores? (2 marks) - This is a past paper question that has come up many times so I think it's useful to learn
    Shorter food chain = more energy converted to growth
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    (Original post by Unknown505)
    What are the environmental effects of building dams to supply water?
    Not sure if its in the spec but its in the Nelson Thorns book
    Destruction of habitats and possible deforestation is all I can think for this one
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    (Original post by MacDaddi)
    Shorter food chain = more energy converted to growth
    Yeah thats one, the other is always that it's cheaper to feed them
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    (Original post by sneakbo2)
    Why do farmers farm Herbivores as opposed to carnivores? (2 marks) - This is a past paper question that has come up many times so I think it's useful to learn
    this is to reduce the stages in the food chain so that more energy can reach the consumer to make biomass

    (Original post by Unknown505)
    What are the environmental effects of building dams to supply water?
    Not sure if its in the spec but its in the Nelson Thorns book
    building dams damages the habitats of animalas and plants, aslo makes neabry areas dry as can dry up rivers, apart from that dunno...
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    (Original post by s.was99)
    Destruction of habitats and possible deforestation is all I can think for this one
    Also infertile and land dryout.
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    why is human urine yellow, when most of its contents are colorless?
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    (Original post by Unknown505)
    why is human urine yellow, when most of its contents are colorless?
    UROBILLINS are in the urine which are the breakdown of haemoglobin in the liver
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    (Original post by Unknown505)
    why is human urine yellow, when most of its contents are colorless?
    As this is because urine contains urobilins, these are made through bthe break down of haemoglobin
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    (Original post by Unknown505)
    What are the environmental effects of building dams to supply water?
    Not sure if its in the spec but its in the Nelson Thorns book
    Dams are created so reservoirs are created. they are breeding grounds for mosquitoes which can pass on malaria
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    (Original post by MrDonIlyas)
    UROBILLINS are in the urine which are the breakdown of haemoglobin in the liver
    Do we need to know about urobillins for tomorrow?? :eek:
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    (Original post by WillowXxx)
    Do we need to know about urobillins for tomorrow?? :eek:
    Thats all we have to know.
 
 
 
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