The diagrams below show two cells. 2013 Marks B Q1 (b) i &ii 1 (i) The plant cell is placed in a hypertonic solution. Describe the appearance of the cell after one hour. (ii) Explain why the animal cell would stay the same size when it is placed in an 2 isotonic solution. Question Acceptable Answer Not acceptable Negates Mark Vacuole/cytoplasm shrunken Other single It/cell 1 (b) i 1 Membrane/cytoplasm pulled away words eg shrinks from wall/cytoplasm concentrated shrunken Plasmolysed/flaccid Plasmolysis ii no net water movement/ Nothing happens Any 1 equal water/osmosis in and out Water does not reference Equal (water/salt) concentration move to inside and out/ no concentration in or out cell wall gradient Solution moving Water/salt equal 1 A model cell was made using a visking tubing bag filled with a starch and amino acid Int 2 Marks solution. It was placed into a beaker of water and left for two hours. 2013 B Q4
2013 B Q1 (b) i &ii The diagrams below show two cells. Marks (i) The plant cell is placed in a hypertonic solution. Describe the appearance of the cell after one hour. 1 (ii) Explain why the animal cell would stay the same size when it is placed in an isotonic solution. 2 Question Acceptable Answer Not acceptable Negates Mark 1 (b) i Vacuole/cytoplasm shrunken Membrane/cytoplasm pulled away from wall/cytoplasm concentrated Plasmolysed/flaccid Other single words eg shrunken Plasmolysis It/cell shrinks 1 ii no net water movement/ equal water/osmosis in and out Equal (water/salt) concentration inside and out/ no concentration gradient Nothing happens Water does not move in or out Solution moving Water/salt equal Any reference to cell wall 1 1 Int 2 2013 B Q4 A model cell was made using a visking tubing bag filled with a starch and amino acid solution. It was placed into a beaker of water and left for two hours. Marks
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