Luis Ordonez
Sabarinath Sundaram
Section 531
Biology Lab 111
External Environmental Factors and Rate of Photosynthesis Abstract- In the first experiment we tested to see the affects that light intensity had on the rate of photosynthesis by creating different environmental conditions.We had hypothesized that the tubes left in the most intense light would have a faster rate of photosynthesis. This experiment resulted in the inhibited rate of photosynthesis when the photosynthetic environment was kept in the dark and wrapped in foil, while the environments that were exposed to light had a gradually increasing rate of photosynthesis as the light intensity of the external environments increased. In the second experiment we tested for the
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In Tube 1, which was held in a dark environment and wrapped in foil, was seen to have almost no change in absorbance relative to the other tubes. The lack of fluctuation in absorbance is a result of very little photosynthesis taking place. Tube 2, which had the most intense light, saw the greatest drop in absorbance in the first 15 minutes. This relatively rapid change in absorbance is a result of photosynthesis occurring more rapidly in this tube than in the others. Tube 3 was put in a similar environment but with less light intensity than in Tube 1 and further away from the lamp than in Tube 1. Tube 3 showed exponential decrease in the first 15 minutes of the experiment but not as drastically as Tube 1. Tube 4 showed a great amount of change, much like the other light-exposed tubes, but because it received the lowest intensity of light, its drop was not as …show more content…
The disks exposed to the green light and to the dark showed the least change in oxygen level and therefore the lowest amount of of photosynthesis occurred. This is most likely due to the fact that the pigment in spinach plants reflect green light instead of absorbing it and going through photosynthesis, and in the dark environment there was no light for the plants to absorb. The beakers placed in the red and blue light showed a greater amount of change than the dark and green light beakers, but they showed a very small amount of change when compared to the beaker in the white light. The white light wavelength was the best for catalyzing
Measuring the Rate Oxygen Production using an Oxygen Electrode Chamber in Photosynthesis of Spinacia oleracea with Varying Light Intensities
Have you ever really wondered how different variables can affect how plants go through photosynthesis? Well, in this experiment, the purpose was to see how various environmental conditions can affect the overall photosynthetic capacity of a specific plant. The factors, light, darkness, cold, and heat were applied to see how the different components would affect the photosynthesis on spinach plants. Each group was given a different factor to test. Out group was given the light factor. The hypothesis for this experiment is that when adding light as a factor, the light will affect the overall plant photosynthesis.
This lab was conducted to discover which level of light (measured in lux) would make Spinacia oleracea leaf disks float the fastest. Lux (lx) is latin for light, and is the unit of measurement for light in the International System of Units (Rouse 2011). Light plays a key role in the process of photosynthesis and in this we are essentially measuring the rate at which Spinacia oleracea leaf disks convert a bicarbonate solution into oxygen. The oxygen then would bubble up, allowing
The ravg for the experimental group was 0.1613 and the ravg for the control group was 0.2047. The results indicated that our predictions were correct; duckweed that received less light exhibited a lower rate of
To performed the experiment, a volumeter was set up to measure the net oxygen production under white light, then a second step was followed to measure oxygen consumption under dark conditions (oxygen production only happens in the presence of light and oxygen consumption in the presence of dark light) and finally, a third step consisted of recording the measure of the net oxygen production under the presence of green light.
The ending result of this experiment confirms that as five test tubes are lined up with the varying level of absorbance, different results in the level of absorbance will appear as well, this is visible in above table. Thus, this is due to the varying amount of water in the solution. The blank sample had a 0.30 in its level of absorbance.
The purpose of this experiment was to investigate the effects of light intensity on the rate of photosynthesis in a Moneywort plant. By observing the plant in distilled water mixed with sodium bicarbonate, different light bulbs were targeted onto the plant. The measurement of the amount of bubbles present on the plant during the trial of the experiment enabled us to identify the comparisons between the activity of the light and the process of photosynthesis.
The rate of photosynthesis is affected by environmental factors like light intensity, light wavelength, and temperature. This experiment will test the
The experiment is repeated twice and an average is obtained. This ensures the consistency of the measurement as the reading is triplicated, thus reducing anomalies. It can be seen that the reading obtained were around the same value. This proves that the results are reliable.
The initial experiment was a success. As our treatment group spent more and more time under the lights, the absorbance rate continues to decrease toward zero. Once our 30 minutes were up, the absorbance rate in each tube was significantly lower than at the start of our experiment. In contrast the two control groups did significantly lower the absorbance. Each control lacked one of the vital aspects of photosynthesis, one being light, and the other being chloroplast. Neither of the control groups (Control 1 or 2) showed any signs of photosynthesis. Control 1 was exposed to light, but contained no photosynthetic organelles thus the absorbance throughout the 30 minutes varied minimally, mostly staying stagnant. Control two which contained chloroplast but was not exposed to any light failed to lower the absorbance at all and in fact increased the absorbance over the 30 minutes. However, the treatment group contained both and ultimately performed photosynthesis as we expect therefore, confirming our assumption that chloroplast were the organelles required for photosynthesis in plants and that light is required to perform said photosynthesis. The treatment group, containing both the chloroplast and being exposed to light provided evidence that photosynthesis was taking place as the absorbance lowered at each 10-minute interval. Having a less absorbance would be desired because as DCIP became reduced we would expect the solution to become more and more clear, thus less
This experiment demonstrates the effects of pH on the rate of photosynthesis by examining the behavior of leaf disks in different pH solutions under light. In this experiment, we used five different pH levels: pH 5, pH 6, pH 7, pH 8 and pH 9. These solutions were created using a combination of hydrochloric acid and sodium hydroxide. Spinancia olcerea or spinach, leaves were used in the experiment to examine the effects of pH on the rate of photosynthesis. The rate of photosynthesis was measured by counting the number of leaf disks that rose to the surface of the solution after each minute. In acidic solutions, the rate of photosynthesis increased while in basic solutions, the rate of photosynthesis decreased.
Although, some factors that could have influenced this experiment was heat given off by the lamps, the restriction of the gas chamber, and how much CO2 there was in the chamber. Photosynthesis is also very heat sensitive, which is why when recording the O2 rates in the dark the lamp still needed to be on. The gas chamber restricted the flow of the natural environment along with already having a certain amount of CO2 in the chamber that wasn’t measured. These could have influenced the
photosynthesis happens in two stages: light reaction and carbon fixation also known as calvin cycle.light reaction TAKES PLACE IN THYLAKOID USE light energy to produces atp and nadph whereas, calvin cycle takes place instroma uses energy derived from light dependent reaction to make GA3P from CO2 ( Bio166 lab execise manual, 2015). the purpose of this experiment was to separate plant
In the test tubes that contained plant sprigs, how did distance from the light source affect the time required to see a color change? How can you explain this result? Test tubes
Photosynthesis is a vital process that autotrophs use to transfer light energy into chemical energy. Photosynthesis ultimately produces O2 and glucose. It, like many other biological processes, can be affected by environmental variables. The variable that we altered in the following experiment are intensity, light wavelengths, and pigment types. In order to do this, we conducted three experiments. In the first experiment, we examined the effect of light intensity by placing vials with chloroplasts with DPIP at different light distances in which the results varied. Initially, 30cm away was the most effective for photosynthesis. Then 24cm appeared to be the most effective. Followed by 49cm at minutes 25 and 30. In the second experiment, we