4 4. An investigation was conducted to find out whether light is necessary for photosynthesis. The procedure followed is given below. BO • A geranium potted-plant was de-starched by placing it in a dark cupboard for 48 hours. A cross-shaped light-slit was cut out on aluminium foil. The aluminium foil stencil was then clipped onto one of the de-starched leaves, as shown in the diagram below. The potted plant was exposed to bright sunlight for 5 hours, After 5 hours, the aluminium foil stencil was removed and the leaf was tested for starch. De-starched leaf Aluminium foil stencil 4.1 Explain why the plant was de-starched. (2) 4.2 Describe the steps, in the correct sequence, that were followed during the starch test. (4) 4.3 Draw a labelled diagram of the leaf showing the result of the investigation. Use a pencil and shade the parts which tested positive for starch. (3) 4.4 Provide a conclusion for this experiment (1) (10)​