bowl onto a test tube rack, was set up. The cuvettes were labeled 1-5. Each was carefully cleaned and prepared as the lab instructed. Cuvette 1 received 1 mL of phosphate buffer and 4 mL of distilled water. Cuvettes 2, 3, and 4 received 1 mL of phosphate buffer, 3 mL of distilled water and 1 mL of DPIP. Cuvette 5 received the same as 2,3, and 4 but there was an extra 3 drops of distilled water added. Cuvette 2 was covered in tin foil so that no light could enter.Once the spectrophotometer was ready, we adjusted the amplifier control until we had a 0% readout on transmittance. We then placed 3 drops of unboiled chloroplasts into cuvette 1 and covered the top with parafilm, and tipped it upside down to mix the contents and quickly placed it into the spectrophotometer. We adjusted it to 100% transmittance. This was used to adjust the machine between readings. Cuvette 1 was placed back on the rack for a period of 5 minutes.Cuvette 2 was our next measurement. It was taken out of the foil and 3 drops of unboiled chloroplasts were added and the top was then covered with parafilm. It was also tipped upside down to mix the contents and was placed into the spectrophotometer.. We took a reading of the percent of light transmittance and recorded the data in the data table. It was then taken out and placed back in its foil and put on the rack.Cuvette 3 was given the same treatment as cuvette 2.Cuvette 4 was given the same treatment as cuvette 3 except that it received 3 drops in the spectrophotmeter.These measurements were repeated every 5 minutes, the last reading was at 15 minute. The spectrophotometer was always recalibrate with cuvette 1. Cleaning the outsides of the cuvettes is a must by the way. After the last measurement everything was cleaned and the spectrophotometer was turned off.Results:This is a table that contains the results from each of the four groups that were performed in the experiment. The average has been cal...
