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Photosynthesis: The Hill Reaction. Announcements. -There is a quiz next week that will cover Fermentation and Photosynthesis . -home work is posted on my web page as usual. Photosynthesis. -Process by which plants, and some bacteria use the energy from sunlight to produce sugar.
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Announcements -There is a quiz next week that will cover Fermentation and Photosynthesis. -home work is posted on my web page as usual
Photosynthesis • -Process by which plants, and some bacteria use the • energy from sunlight to produce sugar. • Also, it is termed “Carbon fixation”. • The overall equation is • 6H2O + 6CO2 ----------> C6H12O6+ 6O2 • -It include two major stages • 1)Light reactions • -it generate energy carrier molecules • ATP and NADPH • -it occur in the thylakoids (Grana) • - Hill Reaction
Photosynthesis 2) Dark reactions or Calvin-Benson cycle - it generate C-C covalent bonds of carbohydrates -it occur in the stroma of the chloroplast
Wavelength and chlorophyll *White light can be separated into different colors (wavelength) by passing it through a prism. *short wave length carry more energy than long wave length
Wavelength and chlorophyll -chlorophyll is the green pigments common to all photosynthetic cells, absorbs all wavelengths of visible light except green. -chlorophyll a is the one that exist in most plants.
Wavelength and chlorophyll • -chlorophyll and other light reaction chemicals are • embedded in the thylakoids membrane. • -chlorophyll a comes in two flavors P700 & P680 • photosystems are Clusters of several hundred • molecules of chlorophyll in a thylakoid. In • eukaryotes Photosystem I uses P700 and • Photosystem II uses P680. • -P700 chlorophyll is sensitive to light energy in • slightly longer wavelength
Light reactions -at which stage DCPIP intercept….. (5-2) -what will happen to the reaction….
Light reactions During electron transport, a proton gradient is generate in the interior of the thylakoids The proton gradient is used to generate ATP through the ADP-ATP pump in a process known as chemiosmotic coupling
I got the picture • we will determine which wavelength • of light are effective in promoting • photosynthesis by determining • photosynthetic efficiency in the • presence of differently dyed • solutions of buffer. • we will be using blue, green, yellow, and red • Wavelength for different colors • blue 430nm, green 520nm, yellow 520nm, and • red 640nm
I got the picture -Also, we will examine the effect of some drugs on the process of photosynthesis. DCPIP---electron acceptor ---blue in oxidized state ---colorless in reduced state Diuron---herbicide DBMIB---herbicide Remember, our endpoint or what we are looking for is the spinach leaf disks to float or at least show indication the reaction started.
I got the picture -by the end of the experiment, you should be able to figure out whether Diuron or DBMIB intercept the reaction before or after DCPIP