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AP Lab 4: Plant Pigments and Photosynthesis. Prelab Discussion!. AP Lab 4 Part A: Pigment Chromatography. What is chromatography? A separation technique that separates molecules by size and solubility. AP Lab 4 Part A: Pigment Chromatography. What will our setup look like?.
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AP Lab 4: Plant Pigments and Photosynthesis Prelab Discussion!
AP Lab 4 Part A: Pigment Chromatography • What is chromatography? • A separation technique that separates molecules by size and solubility
AP Lab 4 Part A: Pigment Chromatography • What will our setup look like? We will substitute a screw-top jar for a graduated cylinder!
Part A: Chromatography • Remember to make a dark pigment line! • Allow pigment to dry between applications. • Do not allow solvent above pigment line at start! Be sure to mark solvent line at end for calculations! solvent
AP Lab 4 Part A: Pigment Chromatography • What is Rf and how do you calculate it? • It is the relationship between the distance moved by a pigment and the distance moved by the solvent.
AP Lab 4 Part B: Photosynthesis • How could one measure photosynthetic rates? • Amount of O2 produced • Amount of glucose produced • Amount of ATP produced • Amount of NADPH created by the reduction reaction: • NADP+ + H+ NADPH
AP Lab 4 Part B: Photosynthesis • We will focus on the NADPH production. • We know that NADPH is the final electron and H receptor in the light dependent reactions. • We will be substituting the compound DPIP (a blue dye to be the final electron acceptor. • Therefore as photosynthesis progresses, the blue dye will become increasingly clear.
sunlight THYLAKOID COMPARTMENT H2O second electron transport system photolysis e– e– ATP SYNTHASE NADPH NADP+ first electron transport system ATP ADP + Pi PHOTOSYSTEM II PHOTOSYSTEM I STROMA Light Dependent Reactions: DPIP! http://www.stolaf.edu/people/giannini/flashanimat/metabolism/photosynthesis.swf Fig. 7.12a, p. 121
Glucose made with ATP energy ATP CO2 reactant Sun = Energy Source Chlorophyll absorbs solar energy NADPH drops off H NADPH H H C C O NADP+ H2O = reactant O O H O H O2 waste Light Dependent Rxns: Thylakoid Membrane Light Independent Rxns: Stroma
AP Lab 4 Part B: Photosynthesis • We will measure the % absorbance with probeware and a colorimeter. • What would a high % absorbance mean reagrding photosynthetic rate? • A low % absorbance?
AP Lab 4: Plant Pigments and Photosynthesis AP Lab 4 Day 2: Take out your flowcharts and lab packets.
sunlight THYLAKOID COMPARTMENT H2O second electron transport system photolysis e– e– ATP SYNTHASE NADPH NADP+ first electron transport system ATP ADP + Pi PHOTOSYSTEM II PHOTOSYSTEM I STROMA Light Dependent Reactions: DPIP! http://www.stolaf.edu/people/giannini/flashanimat/metabolism/photosynthesis.swf Fig. 7.12a, p. 121
Glucose made with ATP energy ATP CO2 reactant Sun = Energy Source Chlorophyll absorbs solar energy NADPH drops off H NADPH H H C C O NADP+ H2O = reactant O O H O H O2 waste Light Dependent Rxns: Thylakoid Membrane Light Independent Rxns: Stroma
Part B: Photosynthesis • Note setup!
Part B: Photosynthesis • Troubleshooting Tips: • Calibrate once! • Two people can calibrate the sensor then help out with the cuvette setup! • Remember to mix each cuvette prior to taking an absorbance reading! • Remember to handle cuvettes by the curved sides and load properly!