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Photosynthesis. ‘Life is a tiny electric current kept moving by the sun’ Svent Gorki. Protocista. Algae. Plants. Photosynthesis Equation. carbon dioxide + water glucose + oxygen 6CO 2 + 6H 2 0 C 6 H 12 0 6. White Light. Electro magnetic spectrum. So Why Green?.
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Photosynthesis ‘Life is a tiny electric current kept moving by the sun’ Svent Gorki
Protocista Algae Plants
Photosynthesis Equation carbon dioxide + water glucose + oxygen 6CO2 + 6H20 C6H1206
Chlorophyll Chlorophyll plays an important role in photosynthesis as it absorbs the energy form the sun Fluorescence of extracted chlorophyll
Chlorophyll Water used SUN 12H2O 6O2 Oxygen produced Light dependent Stage 24 H 6 CO2 Light Independent Stage 6H2O C6H12O6
Extraction of chlorophyll and absorption spectrum Assessment- Data Collection and Processing, Conclusion and Evaluation, manipulative skills Extraction of chlorophyll • Dip fresh leaf material into boiling water first to kill the cells and to make the cell membrane fully permeable to the solvent. • Finely cut about 10g of leaf material (excluding the midrib and petiole) into a mortar and add a small amount of washed and dried sand. • Grind up the leaf matter with 20cm3 of propanone, using a pestle, to make a concentrated leaf extract. • Either filter the pigment solution or decant it (using a glass rod to hold back the debris), and place in a small glass centrifuge tube. Centrifuge the extract briefly, in order to clear all suspended organic matter. • Pour the supernatant solution into a small glass tube, seal with a bung, label it, and stand this chlorophyll extract in the dark, an ice bath, until required.
Measuring absorption of light by chlorophyll • You will be shown how to use either a colorimeter or a spectrophotometer to measure the absorption spectrum of your extract. Once you have done this you will need to plot a graph of absorption against wavelength for the data you collected. • Compare this to the absorption and action spectrums of chlorophyll. How good is your match and how could the experiment be altered to improve your results.