Light Wavelength Lab Report

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.

To measure the rates of photosynthesis by measuring the change in CO2 levels in the air that is in the LeafLab chamber.

In conclusion, the hypothesis is supported by the experiment. Only 2/10 disks floated to the top of the 0.1% NaHCO3 solution, while all 10 of the disks in the 0.2% NaHCO3 solution floated to the top. A potential follow-up experiment could be to test the affects of increased concentrations of carbonation on PS (Bagley et al., 2015). There was the possibility of human error and bias having impact on the experiment. When using syringes, the plunger may have been pulled too harshly and damaged some of the disks. This could have led to disks not floating to the top in the experiment. Another form of error could have been the use of disks that were cut from the veins of the leaf, which has less chloroplasts, meaning less process of photosynthesis happening, and result in the disks not floating to the

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

During the experiment, my partner and I received 0 leaves floating in the 0% concentration which was expected. But we also gathered the data that 0 leaves floated for 0.2% the first time we tried which isn’t expected. The second trial we changed the distance of the light and brought it closer and 4 of our 10 leaves floated in the 15-minute span.

In the beginning of this experiment, our TA added water, salt, and 75/25 hexane/acetone to spinach leaves to a blender and blended the mixture to assume equal amounts for each group and to avoid erros if each student had to do the blending. The addition of the water to the mixture allowed the it to separate into a distinct organic layer after being run in a centrifuge, which was available to be collected at the top of the centrifuge. Salt reduces solubility, which will force the organic parts of the mixture (the desired pigments for example) to separate into the organic layer at the top. Lastly, 75/25 hexane/acetone is added because this is a moderately polar solvent and will useful for both the non-polar and polar pigments present within the spinach leaves. A mixed solution of hexanes and acetone must be used because acetone is very polar, while hexane in very non-polar, and the spinach leaves contain both non-polar and polar pigments in them that are important in the extraction and for further analysis. The mixture was placed in the centrifuge so the solids in the mixture (mostly cellulose) could be separated from the liquids into separate distinct layers for further extraction and testing. In the tube, the organic substances separated into the top layer, whereas the water layer remains at the bottom of the tube below the solid layer made up of mainly cellulose.

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

The purpose of this lab is to observe the effect of white, green, and dark light on a photosynthetic plant using a volumeter and followed by the calculation of the net oxygen production using different wavelengths color of white and green light, and also the calculation of oxygen consumption under a dark environment, and finally the calculation of the gross oxygen production.

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

The rate value of the spinach leaves that were not given light was negative. The negative change in the amount of oxygen can be explained by the fact that, in cellular respiration, one of the reactants is oxygen.

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.

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.

During the separation of the pigments by chromatography paper, chlorophyll b traveled the shortest distance, chlorophyll a went above it, and the highest went beta carotene. This

However, the photosynthetic process can be affected by different environmental factors. In the following experiment, we tested the effects that the light intensity, light wavelength and pigment had on photosynthesis. The action spectrum of photosynthesis shows which wavelength of light is the most effective using only one line. The absorption spectrum plots how much light is absorbed at different wavelengths by one or more different pigment types. Organisms have different optimal functional ranges, so it is for our benefit to discover the conditions that this process works best. If the environmental conditions of light intensity, light wavelength and pigment type are changed, then the rate of photosynthesis will increase with average light intensity and under the wavelengths of white light which will correspond to the absorption spectrum of the pigments. The null hypothesis to this would be; if the environmental conditions light intensity, light wavelength and pigment type are changed, then the rate of photosynthesis will decrease with average light intensity and under the white light which will correspond to the absorption spectrum of the pigments.

The first part of the experiment dealt with breaking down the spinach leaves in a mortar and pestle. Acetone was added to this to help with the breakdown of the spinach leaves. Once the spinach leaves were broke down enough that you could see the particles