Photosynthesis Lab Report 2 PDF

Preview

Summary

Lab report...

Description

Photosynthesis Alisha Bhakta. Biology 1404-Lab Section 0BD. The University of Texas at San Antonio. Spring 2021. 12, 2021. Supervising Instructor: Richard Nuckels/Jennifer Guerrero

April

Abstract In the photosynthesis lab, we are determining the rate of oxygen synthesis and the reducing power of an electron. For the first procedure, we are calculating the rate of oxygen synthesis in the elodea plant. If the color of the light and the exposure determines the rate oxygen synthesis that is produced by the elodea plant, then white light and more exposure would create more oxygen. The second procedure is determining the electron transport in chloroplast through different amounts of various variables. If a tube represents a normal environment where there are no other chemicals represented, then more light will be absorbed, which then creates more oxygen.

Results Table 1

. In this procedure, we are determining the rate of oxygen produced when the elodea plant is placed in a white light setting and in a green light setting. Table 1 shows the values that were recorded from the experiment. The table shows the amount of oxygen that was produced when the plant was in a white light and green light. According to the graph, the elodea plant was able to produce more oxygen when it was placed in a white light compared to when it was placed in a green light setting. The cellular

respiration for both plants were the same because both of them did not receive any light. To calculate the gross photosynthesis, we added the net and cellular respiration for each light. Then we calculated the rate of photosynthesis by multiplying the gross photosynthesis by 6. The reason why we multiply the gross photosynthesis by 6 is because we're determining the rate of photosynthesis by the hour. After we found the rate of photosynthesis, we divided the rate of photosynthesis of the white light from the radar for the synthesis of the green light. After that we were given the class average and divided the class average’s rate of photosynthesis of the white light from the radar for the synthesis of the green light.

Table 2

In this second procedure, we have 5 different test tubes with each tube containing DPIP in them and with other substances. We are testing for how much each chemical substance absorbs light by using a spectrophotometer. Each tube consists of 5ml of DPIP and different tubes contain different amount of chemicals. After the tubes have the necessary chemicals and once, we are done with putting the tubes in front of the light, we note the final color of each tube after 30 minutes. After we note the final colors of each tube, we have to determine the concentration of DPIP in tube 3. To do that, we have to use BeerLambert’s Law. In Beer-Lambert’s Law, A= εlc, each constant has a specific meaning. In this case, we are trying to find C here. A represents O.D. centrifugation, 0.048, ε represents the 21.3mM-1, and l represents the length, which is 1. The equation will look like this C =

0.048O . D . . After we 21.3 mM −1 (1 )

calculate the formula, the answer that we get is 2.25x10^-3 which is then simplified into 0.00225mmol/L.

Conclusions Photosynthesis provides us with most of the oxygen we need in order to breathe. It also eliminates carbon dioxide from the atmosphere. These experiments help us determine how photosynthesis happens and under what state do we get the most out of it. Never did I think that different light colors would affect the rate of oxygen that would be produced. I always thought that the colors did not matter when it came to the production of oxygen. I also did not know that isolated chloroplasts produce oxygen when they are illuminated in the presence of a suitable electron acceptor, even if no carbon dioxide is present. I was not aware of this until when I conducted the experiment. It’s amazing that reducing power of electron transport was landmark in the study of photosynthesis because it indicated that the source of electrons in the light reactions is water, and it confirmed that oxygen comes from water....