Grishma Patel Chloroplast Pigments and Colored Light Absorption Summary The purpose of executing this lab was to see how different wavelengths and colors of light are absorbed by chloroplast pigments. The goal was to see the variations of light dependant reactions of photosynthesis based on different types of light. Spinach was used by grinding it with acetone and acquire the thylakoids used in the experiment. DCIP was used in this experiment as the oxidizing agent that will turn blue to clear when in contact with light. The experiment required us to test first the relationship between wavelength of light and absorbance. The chloroplast pigments from the tissue were used to see which wavelength of light absorbed the most light. The result of this part of the experiment showed that the wavelength 432nm had the highest absorbance of 0.286. Next, we tested the absorbance of different colored lights. This part of the experiment tested the results of absorbance of red, green, white, purple, blue and no light using DCIP. Blue light showed the highest absorbance. Finally we found the chromatography pigments of different bands based on the separation of photosynthetic pigments. Methods Materials The materials used in the …show more content…
The test tube was closed and shaken with a stopper which was periodically removed to alleviate pressure. The test tube was then left on the test tube rack to allow the solvents to separate. It had separated with the ether phase on top and acetone phase on the bottom. To see what light was being reflected, the tube was taken to the projector and it was recorded that the light reflected was red. The ether phase was used to paint with a brush approx. one inch above the bottom of a six inch chromatography paper. This step was repeated time
For this lab, zeolite and magnetized zeolite were synthesized and compared with charcoal to find out with would be the most effective in the sequestering of Procion Red dye. Finding the concentration and absorbance of each zeolite, magnetized zeolite, and charcoal, along with a calibration curve, the best adsorbent is determined. Charcoal was the overall best sequestration of the Procion Red dye, since the adsorbent was highest compared to the others. Introduction Pollution has increased in the environment over the years, so the purpose of this experiment is to find the best adsorbent of chemicals to reduce the pollution.
In the first part of the experiment, Part A, the standard solutions were prepared. As a whole, the experiment was conducted by four people, however, for Part A, the group was split in two to prepare the two different solutions. Calibrations curves were created for the standard solutions of both Red 40 and Blue 1. Each solution was treated with a serial 2-fold dilution to gain different concentrations of each solution.
The wavelength of light emitted by sodium light sources is made up of yellow wavelengths from 589.0 - 589.6nm so no colour version is possible. These lights may not be ideal at night time this is because, the human eye cannot function fully in the photopic state, and its colour sensitivity shifts to the scotopic night vision conditions. This phenomenon is known as the Purkinje shift. Herein lies a deficiency of our measure of light because it is based on the normal daylight sensitivity curve of the eye.
That mixture was then filtered through a coffee filter. Nine test tubes were prepared in order to perform this dye coupled reaction. One contained 5.0ml of the potato and pH buffer mixture, 2.0 ml of hydrogen peroxide, and 1.0 of guaiacol to serve as a blank for the spectrophotometer. Four test tubes were filled with 2.0 ml of hydrogen peroxide and 1.0 ml of guaiacol, used for measurement by the spectrophotometer, each. The last four were filled with 4.0 ml of the potato and pH buffer mixture and 1.0 ml of peroxidase.
Something that was interesting to find out though, in the description of the reagent color test they show the lighter color on top and the darker one on the bottom. But just as the test that was conducted showed and what Officer had said was that the darker color is always on the top and the lighter on
Trichromatic theory first proposed Thomas Young and later modified by Hermann Von Helmholtz proposed three types of cones photoreceptors knowns as red cones, green cones and blue cones. The cones are sensitive to specify wavelengths of light that later fire the signal to the brain. Where by the combination of cones and the rate of firing determine the color will been sight. These theories were test through psychophysical color matching experiment (Figure 1), to study the light wavelength signaled by activity of three receptor mechanisms. The research identify that the three different cones have differ maximal sensitivity that corresponds to three different color.
Record the amount of absorbance by converting transmittance every 5 minutes for a total of 20 minutes. Repeat all of these steps for the cantaloupe, banana, replacing the blank each time to recalibrate the spectrophotometer. After recording all the percent transmittance value, the data was then converted into absorbance value by using the absorbance conversion table. The information was placed on a plotted graph
Because carbon dioxide is absorbed by the plant during photosynthesis less carbon dioxide present in the chamber is a sign that photosynthesis is working. The four lights used for this experiment range across the light spectrum on both sides in order to test a wider variety of wavelengths. All lights will be placed directly on the spinach leaf at the same distance so as not to give any spinach leaf a different light intensity, which could affect the data. This experiment will be able to show which light, ranging across the light spectrum, will allow the Spinach to perform photosynthesis more efficiently.
LABORATORY REPORT EXERCISE #5 INTRODUCTION TO THE COMPOUND LIGHT MICROSCOPE, PLANT AND ANIMAL CELLS Name_______________________________Section_____Teacher______________Date________ PRE-LAB QUESTIONS - answer the following questions using your textbook and valid internet sources. Be sure to cite your sources at the end of the prelab. You can type your answers to all questions except #1 and #9 directly into this document and then submit via Canvas. Type the answers for #1 and #9 at the end of the document. 1.
The first experiment involved in this four-week project was the extraction and
Jaspreet Singh Professor Paratore Biology 1 November 1, 2014 Spectrophotometry Identifying Solutes and Determining Their Concentration Statement of the Exercise or of the Problem The purpose of the lab experiment was to attain the following objectives: • Learning to Operate the Spectrophotometer • Construct absorption spectra for cobalt chloride and chlorophyll. Hypothesis If greater and higher concentrations of cobalt chloride are added to each solution then greater amounts of light would be absorbed by each solution. Thus a liner relationship will result in which the absorbance of a substance would be proportional to its concentration, which will be depicted, in a linear graph.
The 3 concentrations of enzymes were 0.5 ml, 1.0 ml, and 2.0 ml of turnip extract, while the substrate consisted of 0.1ml, 0.2 ml, and 0.4 ml of hydrogen peroxide. In a separate tube, the control was made up of turnip extract and guaiacol, known as the color reagent. This was recorded the absorbance every 20 seconds for 3 minutes.
The absorbance level @ 520 nm obtained from the spectrometer indicates the amount of urea obtained via measuring the absorbance of the light through the supernatant coloration, which was provided by the
Column chromatography set-up After setting up the column, 2 10-ml of the chosen solvent was obtained and was placed in two separate test tubes. Using a dropper, ~0.5 mL of the food dye was put into the column by dropping it at the side of the column in a circular motion. The chosen solvent was then added just after the green food
This ability make the animals blend with their surroundings not only for camouflage but also for communication such as during mating. The pigment cells (chromatophores) are responsible for releasing the pigment into the outer layer of animal’s skin. The pigmented chromatophores with its variety of colors (e.g. yellow, red, orange, brown, black, blue and green) can -when used in combinations- are responsible for the numerous colors which cuttlefish can display. It is claimed that cuttlefish are the fastest color changers in the whole animal kingdom.