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Medicine LibreTexts

3.17: Diffusion and Osmosis Worksheet 2 Answers

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  • 1. Circle the correct answer.

    a) When red blood cells are placed in an isotonic solution they:stay the same
    b) Red blood cells are isotonic to: 0.9% salt solution
    c) Red blood cells placed in a 2.0% salts solution would: shrink.
    d) Red blood cells placed in distilled water would: swell
    e) When red blood cells are placed in distilled water: the water enters the cells
    f) Red blood cells placed in a 0.9% salt solution would: stay the same
    g) Red blood cells placed in distilled water are in a: hypotonic solution.
    h) Red blood cells placed in 0.9% salt solution are in an:isotonic solution
    i) Red blood cells placed in a 2.0% salt solution are in a:hypertonic solution.
    j) A dialysis bag (made of an artificial semi-permeable membrane) filled with 0.5% salt solution and placed in a beaker containing 3.0% salt solution will: shrink.

    2. Three bottles are filled with three different solutions. One with distilled water, one with 0.9% salt solution and the third with 9.0% salt solution. A few dried apricots are placed in the three bottles and left in the solutions for an hour.

    The apricots in bottle A stay the same.
    The apricots in bottle B shrink
    The apricots in bottle C swell.

    Now answer the following questions:

    i) Which bottle contains the most concentrated salt solution? B
    ii) Which bottle contains water? C
    iii) Which bottle contains the isotonic salt solution? A
    iv) Which bottle contains the hypotonic solution? C
    v) Which bottle contains the hypertonic salt solution? B

    3.A semi - permeable membrane (dialysis) bag, containing 4% salt, 4% glucose and 4% albumin is suspended in distilled water. Assume the bag is permeable to all substances except albumin.

    Semipermeable membrane bag experiment 2.JPG

    a) The salt: moves out of the bag
    b) The water: moves into the bag
    c) The albumin: does not move
    d) The glucose: moves out of the bag
    e) The salt moves by: diffusion
    f) The water moves by: osmosis
    g) The albumin moves by: it does not move because the molecules are too large.
    h) The glucose moves by: diffusion


    Ruth Lawson (Otago Polytechnic; Dunedin, New Zealand)