In conclusion, the analysis of the absorption spectrum of coleus leaves has revealed valuable insights into the pigments present in the leaves and their efficiency in capturing light energy for photosynthesis. The differences in absorbance and transmittance observed between green and red coleus leaves suggest the presence of various pigments that contribute to the photosynthetic characteristics of different parts of the plant. The absorption spectrum graph depicted high absorbance values in the range of 400 nm to 480 nm, indicating high energy levels associated with shorter wavelengths. The transmittance data showed that most wavelengths were reflected back, indicating the utilization of light for photosynthesis by the pigments present in the leaves.
Overall, the study of absorption spectra in coleus leaves has provided a deeper understanding of the mechanisms of photosynthesis and the role of pigments in light capture. The presence of pigments such as chlorophylls, carotenoids, flavonoids, anthocyanins, and betalains in coleus leaves contributes to their vibrant coloration and their ability to efficiently capture and utilize light energy. Further research in this area can enhance our knowledge of plant biology and contribute to the development of more sustainable agricultural practices. By continuing to explore and analyze absorption spectra in plant leaves, we can unlock the potential for improved crop productivity and ecological sustainability.
Title: Finding the Absorption Spectrum of Coleus Leaves.
Introduction:
An absorption spectrum is the range of wavelengths of light that a substance can absorb. It is crucial for understanding the pigments and molecules present in leaves that capture specific wavelengths of light for photosynthesis. Leaf spectroscopy, which involves measuring the light reflected or absorbed by leaves, is a popular and non-destructive method for evaluating leaf biochemical and physical parameters such as pigment content and chlorophyll levels.
Research has focused on characterizing different types of leaves and building databases of various color ranges. Studies have quantified light absorption in isolated chloroplasts and leaves with varying pigment content, as well as in coleus plants at different stages of leaf development. By comparing absorption spectra of leaves and chloroplasts, researchers have observed changes in the extent of the 'package effect' and the effective optical path length in leaves. The difference between leaf and isolated chloroplast absorption can be explained by a modification of Duysens's flattening model, indicating that as chlorophyll accumulates in leaves, the 'package effect' strengthens. Studying absorption spectra in leaves provides valuable insights into the mechanisms of photosynthesis and the role of pigments in capturing light energy. Further research in this area can enhance our understanding of plant biology and contribute to the development of more efficient agricultural and ecological practices (Habibullah M, Mohebian MR, 2015).
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Aim:
The goal is to analyze the absorption spectrum of a sample in order to understand which wavelengths are most effectively utilized by pigments in various colored leaves.
Materials:
The equipment needed includes a balance, coleus leaf, mortar and pestle, 30 mL of ethanol, 35 mL syringe, 100 mL beaker, funnel with a coffee filter, 2 cuvettes, Kimwipes, Sharpie marker, small test tube rack, spectrophotometer or calorimeter, and a weight balance.
Procedures:
To start, extract chlorophyll by grinding 0.3 grams of variously colored coleus leaves in a mortar with 10mL of ethanol. Add an additional 20mL of ethanol to the mixture and filter the extract using filter paper. Transfer the extract solution to a cuvette and measure the absorbance at various wavelengths ranging from 400 nm to 700 nm using a spectrophotometer. Record the measurements in a table and use the data to create an absorption spectrum graph.
Note: The leaves were green and red, two different groups tested the different coleus leave. The first group tested the green coleus leaves and the second group tested the red coleus leaves. For the sample extraction and methods carried out was same.
Results: Table One. The following chart displays the absorption and transmission of light by red coleus leaves at different wavelengths.
Wavelength Green sample Absorbance Transmittance
400nm
7 20
420nm 5.8 27
440nm 5.3 30
460nm 6 25
480nm 4.5 36
500nm 2.7 54
520nm 2.5 57
540nm 0.4 92
560nm 2.3 58
580nm 2.5 56
600nm 2.4 58
620nm 2.45 57
640nm 0.4 91
660nm 0.8 83
680nm 0.85 82
700nm 2 63
Table 2: Green Coleus Leaves. The table displays the wavelengths of light, the amount of light absorbed, and the amount of light transmitted through green coleus leaves.
Wavelength Green sample Absorbance Transmittance
400nm
7 20
420nm 5.8 27
440nm 5.3 30
460nm 6 25
480nm 4.5 36
500nm 2.7 54
520nm 2.5 57
540nm 0.4 92
560nm 2.3 58
580nm 2.5 56
600nm 2.4 58
620nm 2.45 57
640nm 0.4 91
660nm 0.8 83
680nm 0.85 82
700nm 2 63
The graph shows the amount of light absorbed by green and red coleus leaves at different wavelengths.
The transmittance of green and red coleus leaves was compared.
Discussion
Differences in the wavelength, absorbance, and transmittance of photosynthesis pigments were observed in the analysis of coleus leaves. These differences indicate that various pigments are present in the leaves, which can affect the photosynthetic characteristics of different portions of the plant. Transmittance refers to the wavelengths of light that pass through a sample, while absorbance refers to the wavelengths of light that are not passing through but are being used by the sample. The absorption spectrum graph showed high absorption values in the range of 400 nm to 480 nm, indicating high energy levels due to the shorter wavelength values. As the wavelength increased from 480 nm to 700 nm, the energy levels decreased. The transmittance data revealed that most of the wavelengths in the coleus leaves were refracted back, as indicated in the table. Different pigments were absorbed at different wavelengths during the process, with chlorophyll a forming in the range of 400 nm to 500 nm. The presence of pigments such as Chls, Cars, flavonoids, anthocyanins, and betalains in coleus leaves contributes to their coloration. In higher plants, Chlorophyll a, b, and C are responsible for light harvesting, with Chl a passing absorbed light energy into the electron transport chain. The absorption spectrum analysis of coleus leaves provides insights into the types of pigments present, their efficiency in capturing light, and their contributions to the overall process of photosynthesis in plants.
using the above imformation, generate a best and outstanding conclusion
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