In this examination, four tubes of the chloroplast (Dark, 24cm, 30 cm, and 49 cm), buffer solution, water and DPIP were set in different strengths of light to decide how the light, powerful influences the reaction rate. The response rate was measured using absorbance values in five-minute increments. The tubes were put at 24 cm away, 30 cm away, 49 cm away, and totally dull. The tube nearest the light caused the smallest absorbance value, while the dim tube had the most astounding absorbance values. As the light power builds, the absorbance esteem and rate of the response diminished.
Introduction:
In this lab, DPIP was found as a substitute for NADPH in the electron transport chain to value the impact of illumination intensity on electron transport
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Each of the solutions and their respective blanks was put through a spectrometer at various wavelengths- increasing by increments of 50 nm each trial. The wavelengths of 400 nm to 500 nm had the best absorption rates.
Introduction:
The Four pigments: Carotene, Chlorophyll a, Xanthophyll, and Chlorophyll b are necessary when photosynthesis takes place in the stomata. The aim of this lab was to see how wavelength affected the rate of photosynthesis. My theory was the four pigments would have higher optical density with a shorter wavelength than the longer wavelength. While my null hypothesis was the different wavelengths will have no consequence on the observed levels of the four different pigments.
Methods:
Four pigments were procured from the technical assistant with blanks. The spectrophotometer was turned on to 400 nm. Once it was ready to use, the pigments were passed through to spectrophotometer one by one and recorded. Once the first trial was done, the spectrophotometer was increased to 450 nm. This process continued in 50 nm increments until the spectrophotometer is at 700 nm. After the 700-nm trial, the spectrophotometer can be turned
The dyes in the laboratory experiment are made of numerous colors, mainly red and blue, the spectra from each of the dyes corresponded to the wavelengths obtained from each of dye i.e. 620 nm for red and 450 nm for blue.
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
Experiment 1 Question: The main question that was addressed in the first experiment (Parts I and II) was which cell fraction had the most photosystem activity, which would be proportional to the number of chloroplasts present in the cell fraction. Photosystem activity is proportional to the number of chloroplasts since the photosystems are active in the thylakoid membranes of chloroplasts (Leicht and mcallister 2016). The amount of photosystem activity would be seen in the relative absorbance values for each cell fraction under the given light conditions. The absorbance would decrease as the DCIP electron acceptor (which is blue when oxidized) gets reduced (which is colorless). “The amount of color change is expected to be proportional to the number of functional photosystems, which in turn is proportional to the number of intact chloroplasts” (Leicht and mcallister 2016). We knew that chloroplasts were required for photosystem activity, but we
During photosynthesis, the section that is light dependent stage is in the thylakoids in the Mitochondria of a plant cell, while the light independent stage is in the stroma of the Mitochondria of a plant cell, specifically named the Calvin cycle. The light dependent and light independent stage work together to perform photosynthesis. The light independent gives ATP and NADPH to the light independent stage. In return, the light independent stage gives the light dependent stage NADP+ and ADP. The light dependent stage works in the thylakoids of the Mitochondria in a plant cell. It starts off by light energy being absorbed by photosystem II,
An analytical wavelength was the wavelength at which a color of the visible light spectrum will experience the strongest absorption, and the less diluted solutions with higher concentrations will absorb more of the transmitted light. Once the B1 and R3 dyes have their absorbencies calculated, the experiments can then attempt to answer the guiding question, “how could you make 1-L of Pirate-Purple dye solution?” The guiding question was related to the background information because the background information was necessary to use absorbency and molarity to understand how to make 1-L of Pirate-Purple dye solution. Absorbency can be used to find molarity by using an equation for the slope of a graph made during the pre-lab which describes the relationship between concentration and absorbency, the equation was ( y=m(x)+b). In the equation,
The Effect of the Light Intensity on the Rate of Photosynthesis Introduction: There are many factors that effect the rate of photosynthesis in plants. Some of the factors that impact photosynthesis is temperature, amount of sodium bicarbonate, water temperature, the size of the plant that undergoes photosynthesis, and light intensity. This lab will concern light intensity. The lab will address the outcome of having a really high light intensity compared to a really low light intensity during photosynthesis.
There are two photosystems, PS I and PS II. PS I has a 700 nm absorbing chlorophyll a P700 molecule at its reaction centre, while PS II has a P680 reaction centre that
During this lab, spectroscopy and chromatography was used to determine the various properties and characteristics of fast green solution, chloroplasts and an unknown solution. The spectrometer helped determine the absorbance levels of each substance which was used in this experiment. The levels which were determined were used to find the concentration curve of the concentrated solution of fast green solution and the concentration of the given unknown 215. The chlorophyll solution presented a varied distribution in the absorbance levels which would eventually help us determine what wavelengths are absorbed by chlorophyll. Chromatography was used to separate the components of the chlorophyll (spinach) solution which revealed
For lab 12, it is hypothesized that chlorophylls a and b are present in a plant leaf and contribute to the starch production in photosynthesis. Also, products of photosynthesis will be present in leaf tissue exposed to red and blue light wavelengths for several days, but a decreased presence in leaf tissue exposed to green and black light wavelengths. In lab 13, it is expected that since chlorophylls a and b are more polar and smaller molecules than the anthyocyanins and carotenoids, they will travel higher up the chromatography paper than the other pigments.
concentration, record the absorbance readings at a fixed wavelength, and plot the absorbance vs. concentration data. The wavelength of 520 nm was selected for experiment Part
In order to survive, all organisms need to have a source of energy. Photosynthesis is the process by which plants use light energy and simple molecules to make chemical energy. The majority of all living things on earth benefit either directly or indirectly from the ability of photoautotrophs to do photosynthesis. Plants provide oxygen to Earth’s atmosphere and all animals, including humans, depend on plant material for food or to feed the food that they ultimately consume. Photosynthesis takes place inside the chloroplasts of a eukaryotic cell. Many factors affect the rate of photosynthesis in photoautotrophs including temperature, carbon dioxide concentration, the presence of water, and light intensity.
As a control for the effect of temperature, one of the samples was kept at room temperature which is 25° C (Tube 3). Since the experiment we conducted on September 23, 2010 during Biology Lab 101 was conducted at room temperature, we had baseline data for what the rate of photosynthesis at this temperature would be. We concluded that this data could be used as a control to compare the rates of photosynthesis in both our experimental tubes. This tube was housed in a water bath set to 25° C. Contents of this tube included 1 mL of DPID, 1 mL of the buffer solution, 3 mL of water, and 3 drops of chloroplasts.
Following, placing the Gatorade sample into a cuvet and place it in the spectrometer and look for the wavelength that was recorded in the stock dye samples
After 20 minutes, set the wavelength (λ) to 405nm. Keep the pH at a constant of 8 and the temperature at a constant of 37°C. Use a blank, and place inside the spectrophotometer. By doing this you are making the absorbance reading zero as to get future accurate absorbency readings. Prepare 9 test tubes (cleaned and dried) according to the table
In this lab, we experimented with the photochemical reactions of photosynthesis. In the first experiment, by putting test tubes at different distances from a light source, we tested the effects of light intensity. In the second experiment, the effects of light wavelengths and pigments were tested on spinach disks under different colored lights over time to see which light could float the most disks. In the third experiment, by using photosynthetic pigments, we measured absorbance to see which wavelengths of light were used for photosynthesis.