Biology Lab

Studying the Rate of Photosynthesis and Influence of Pigments

Travis Johnson

Biology 240

Section 002

Dr. Michael R. Gannon

April 11, 2012

Abstract:

According to Life, “Photosynthesis is a metabolic process by which the energy of sunlight is captured and used to convert carbon dioxide and water into sugars”(Sadava, 2011). Photosynthesis is the source for how plants get their food. They can absorb this light energy by using chlorophyll pigments that eventually form sugar in the form of ATP and NADPH. The availability of sugars made by photosynthesis for plants determines how well the plant grows. During the lab we performed three separate experiments: Rate of Photosynthesis, Products of Photosynthesis, and Photosynthetic pigment chromatography. Each of these experiments tested how various conditions of plants could withstand plant growth and see how much the plant is photosynthesizing. The closer a plant is to sunlight, the faster its photosynthetic rate. When plants were grown in various light conditions, iodine was detected only in areas where light had hit the plant. In the third experiment it was concluded that by-products Chlorophyll b, Lutin, and Carotenes were made from the photosynthetic process.

Introduction:

Methods:

During this experiment three different parts were set up and completed to gather a variety of data. The parts were labeled “Rate of Photosynthesis” (Part 1), “Products of Photosynthesis” (Part 2), and “Photosynthetic pigment chromatography” (Part 3). Each of these experiments has different steps and equipment that must be followed to get accurate results.

The Rate of Photosynthesis was performed using leaf disks that were infiltrated with bicarbonate solution. A number of leaves off a fresh Snake Plant (Sansiveieria trifasciata) were rinsed with water and 5 disks were cut out using a cork borer. The leaves were placed in a tube that had sodium bicarbonate solution (0.016M NaHCO3) and evacuate the tube with an...