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    Can some1 explain the answer to this question I don't get why the answer would be a
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    Part B:
    Remember your definitions:
    Diffusion: The passive movement (requires no energy) of molecules from a high concentration to a low concentration.

    Osmosis: Movement of water molecules from an area of high water potential to an area of low water potential through a semi-permeable membrane.

    Respiration: Production of energy by a cell, which may or may use oxygen.

    Answer: Since the question is only talking about the movement of oxygen molecules into a cell, the correct answer is diffusion. There is no reference to the production of energy (respiration)

    Part A:
    It's all about the diffusion gradient - i.e. the difference in concentration outside and inside the cell. The greater difference in concentration, diffusion will occur faster.

    As we said in our definition, diffusion always moves molecules from a high concentration to low concentration until the concentration either side of the barrier is equal - it has reached equilibrium.

    Cells B and D: concentration is equal either side of the barrier (in our case, the cell wall). There is no diffusion gradient, so diffusion doesn't occur.

    Cell C: High concentration inside the cell, low concentration outside - there is a diffusion gradient. However this gradient will cause oxygen to move out from the cell.

    Cell A: High concentration outside, low concentration inside - there is a diffusion gradient. Oxygen moves into the cell.

    Correct answer: A.


    If you need more help, feel free to PM me. Stay happy!
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    Diffusion is the net movement of ions or molecules from a high to low concentration.

    The answer would be A because there is a greater concentration gradient.(a greater difference in concentration on either side of the exchange surface)

    There is a lower concentration inside, and a higher concentration outside, so more oxygen will moves inside (In A)

    Hope this helps!
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    (Original post by JonBr)
    Part B:
    Remember your definitions:
    Diffusion: The passive movement (requires no energy) of molecules from a high concentration to a low concentration.

    Osmosis: Movement of water molecules from an area of high water potential to an area of low water potential through a semi-permeable membrane.

    Respiration: Production of energy by a cell, which may or may use oxygen.

    Answer: Since the question is only talking about the movement of oxygen molecules into a cell, the correct answer is diffusion. There is no reference to the production of energy (respiration)

    Part A:
    It's all about the diffusion gradient - i.e. the difference in concentration outside and inside the cell. The greater difference in concentration, diffusion will occur faster.

    As we said in our definition, diffusion always moves molecules from a high concentration to low concentration until the concentration either side of the barrier is equal - it has reached equilibrium.

    Cells B and D: concentration is equal either side of the barrier (in our case, the cell wall). There is no diffusion gradient, so diffusion doesn't occur.

    Cell C: High concentration inside the cell, low concentration outside - there is a diffusion gradient. However this gradient will cause oxygen to move out from the cell.

    Cell A: High concentration outside, low concentration inside - there is a diffusion gradient. Oxygen moves into the cell.

    Correct answer: A.


    If you need more help, feel free to PM me. Stay happy!
    thanks 4 ya help I understand this topic much more now appreciate it!!!
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    (Original post by boos63)
    Diffusion is the net movement of ions or molecules from a high to low concentration.

    The answer would be A because there is a greater concentration gradient.(a greater difference in concentration on either side of the exchange surface)

    There is a lower concentration inside, and a higher concentration outside, so more oxygen will moves inside (In A)

    Hope this helps!
    Thank you xx
 
 
 
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