In an experiment to investigate a factor affecting photosynthesis, a leaf of a potted plant which had been kept in the dark over
night was covered with aluminum foil as shown in the diagram below 1. Aluminium foil The set up was kept in sunlight for three hours after which a food test was carried out on the leaf. (a) Which factor was being investigated in the experiment? b) What food test was carried out? (i) State the results of the food test (ii) Account for the results in c (i) above
The photosynthetic activity of the plant was being investigated in the experiment and no photosynthesis will occur because the aluminium foil reflect 95% of sunlight. Starch test is the food test that was carried out in the experiment. Starch from plants is broken down into its constituent sugar molecules by the plant body in order to provide energy to the tissues so if there is no photosynthesis occurs, the plant body uses starch so decrease occur in the concentration of the starch molecules when the starch food test will occur.
