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PHOTOSYNTESIS. IS THE PROCESS IN WHICH SIMPLE ORGANIC MOLECULES ARE TRANSFORMED INTO COMPLEX “ENERGETIC” ONES. SOLAR ENERGY IS REQUIRED. CO 2 + H 2 O ------------- > C 6 H 12 O 6 + O 2. -(CH 2 )--(CH 2 )-- C-OH C=O C=O OH O=C=O. ENERGY.
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PHOTOSYNTESIS IS THE PROCESS IN WHICH SIMPLE ORGANIC MOLECULES ARE TRANSFORMED INTO COMPLEX “ENERGETIC” ONES. SOLAR ENERGY IS REQUIRED.
-(CH2 )--(CH2 )-- C-OH C=O C=O OH O=C=O ENERGY
CO2 + H2O -------------> C6H12O6+ O2 + ENERGY Endergonic Reaction
RESPIRATION FOOD ATP Respiration is the chemical process that transform the energy of food into a universal chemical compound called ATP.
Title ADENOSIN DIPHOSPHATE (ADP)
Title ADENOSIN TRIPHOSPHATE (ATP)
CO + H O C H O + O 2 2 6 2 6 12
CO + H O C H O + O 2 2 2 6 12 6 + ENERGY Exergonic reaction
Title Thylacoid Stroma Inner Membrane Outer membrane CHLOROPLAST
LIGHT (ENERGY) H 2O LIGHT-DEPENDENT REACTIONS O2 ATP, NADPH CO2 LIGHT-INDEPENDENT REACTIONS CHO
INSIDE THYLACOID
Light- Dependent Reactions • One of three processes occurs when light strikes an object; • Light is absorbed (drives photosynthesis) • Light is reflected (makes objects visible) • Light is transmitted (makes objects visible)
Chlorophyll • Chlorophyll, the key light-capturing molecule in thylakoid membranes, strongly absorbs violet, blue, and redlight but reflects green (thus that is what our eyes see). • Thylakoids also contain other molecules, called accessory pigments that capture light energy and transfer it to chlorophyll. • Carotenoids absorb blue and green light and reflect mostly yellow, orange or red. • Phycocyanins absorb green and yellow and thus we see the blue or purple wavelengths
Light- Dependent Reactions • In the thylakoid membranes, chlorophyll, accessory pigment molecules, and electron-carrier molecules form highly organized asseblies called photosystems
Q FeS + H Pq Fd cit f Fad - + Pc 2e NADP NADPH P700 (FS I) P680 (FSII) + H + O H O 2 2
Light- Dependent Reactions • There are two different photosystems • Photosystem I • Photosystem II
Light- Dependent Reactions • The light-harvesting complex is composed of about 300 chlorophyll and accessory pigment molecules that absorb light and pass the energy to a specific chloropyll molecule called the reaction center • Thus these pigments act as antenae to direct the light energy to the electron transport system
ATP ADP+Pi H2O [H+] H2O
CO2 2 ATP 2 2 ADP H2 C-O-P | COH | C-O-P || O H 2NADPH ADP 2 P 2 NADP + ATP H2 COH | C=O | COH | COH | C-O-P H2 C-O-P | COH | C-H || O H H H H2 H2 C-O-P | COH | C=O | OH H2O H H2 C-O-P | C=O | COH | COH | C-O-P H CALVIN CYCLE H H2 Glucose