Photosynthesis

• Photosynthesis Raw materials: 6 CO2 + 6 H20 + SUNLIGHT = 6 O2 (by product) + C6H12O6 (1 molecule of glucose / End product)
• Chlorophyll absorbs light energy (photon), which is used to convert carbon dioxide into glucose.
• Photosynthesis: the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.
• Photosynthesis in plants generally involves the green pigment chlorophyll and generates oxygen as a by-product
• Photosynthesis: Light dependent reaction (Photochemical stage): occurs in thylakoid membrane
• Photosynthesis: Light independent reaction/ Dark reaction (Calvin cycle) occurs in stroma
• Photons strikes the thylakoid and water is used to produce ATP and NADPH (Nicotinamide Adenine Dinucleotide Phosphate) which are energy molecules = O2 (by product)
• CO2 + NADPH + ATP will be processed in the stroma to produce = GLUCOSE ( end product)
• Light Independent Reaction: Occurs in Stroma, converts CO2 into glucose using ATP and NADPH produced during the light dependent reaction.
• Chloroplasts contain two types of photosystems - PSI and PSII
• The Calvin Cycle consists of three stages: Carbon Fixation, Reduction, Regeneration
• Carbon fixation: The first step in the Calvin cycle where carbon dioxide is fixed onto ribulose bisphosphate (RuBP), forming unstable six-carbon compound called an intermediate
• Reduction: In this step, the enzyme Rubisco catalyses the conversion of the unstable six-carbon compound into two molecules of glyceraldehyde 3-phosphate (GAP). This process requires ATP and NADPH from the light-dependent reactions.
• PSI and PSII work together to split water molecules and generate ATP and NADPH
• ATP synthase uses ADP and Pi to form ATP
• Regeneration stage regenerates RuBP by combining one G3P with another molecule of CO2.
• Chlorophyll a absorbs most strongly at blue and red wavelengths
• Chlorophyll b absorbs more strongly than chlorophyll a at orange/red wavelengths
• Plastids: Chloroplast - contains green pigment (chlorophyll)
• Plastids: Chromoplast - contains yellow (carotenoid) , red (phycoerythrin) , blue (xanthophyll)
• Plastids: Leucoplast - colorless plastids contain organic substances (oil, starch, protein)
• Centrioles: Small cylindrical dark bodies, Pairs called diplosome, Found outside the nucleus, Formation of spindle fibers