CHEM 103 Lecture Notes - Lecture 6: Thylakoid, Leaf, Light-Dependent Reactions
Document Summary
All life on earth depends on solar energy. Photosynthetic organisms (algae, plants, and cyanobacteria) transform solar energy into the chemical energy of carbohydrates. Called autotrophs because they produce their own food. Photosynthesis takes place in the green portions of plants. Cells containing chloroplasts are specialized to carry out photosynthesis. The raw materials for photosynthesis are carbon dioxide and water. Roots absorb water that moves up vascular tissue. Carbon dioxide enters a leaf through small openings called stomata and diffuses into chloroplasts in mesophyll cells. In stroma, co2 is combined with h2o to form c6h12o6 (sugar) Chlorophyll and other pigments absorb solar energy and energize electrons prior to reduction of co2 to a carbohydrate. Light reactions take place only in the presence of light (energy-capturing reactions) Used to make atp out of adp and nadph out of nadp. Calvin cycle reactions take place in the stroma. Pigments found in chlorophyll absorb various portions of visible light.
