Ch 6 Photosynthesis

Chapter 6: Photosynthesis Electromagnetic Spectrum: Gamma (>10-12) – X-Rays (10-12) – Visible Spectrum (10-6) – Radar (10-4) – Micro (10-2) – TV/Radio (<104)

Photosynthesis: conversion of energy from sunlight into energy in chemical bonds (carbohydrates) • Inside the chloroplast, the is a chemical – chlorophyll – which captures energy from the sun and, along with water, produces ATP + NADPH + O2 (Light Reaction) (inside thylakoids) o ATP: a nucleotide called adenosine triphosphate; a form of stored energy • Then, ATP + NADPH, along with CO2 are used to produce glucose (C6H12O6), a form of stored stable energy (Dark Reaction) (inside the stroma) o 1/6 converted ATPs make glucose, while the others are used to keep the cycle going. It takes energy to make energy. Grana: stacks of thylakoids in chloroplasts Thylakoids: coins with membranes that are used to perform photosynthesis Stroma: space between grana in chloroplasts

Carbon Fixation: • C3 plants fix carbon from CO2 • C4 plants (grass, sugar cane, corn) fix carbon during the day • CAM plants (cactuses) fix carbon at night C4 Plants: store carbon with enzymes, then break it down into C3 CAM Plants: plants in the desert, or other hot environment; shut down all day, pull in CO2 at night through stomata, then fix it; long, slow process Dark Reaction: ATP + NADPH + CO2  ADP + NADP+ +C6H12O6 Light Reaction: ADP + NADP+ + sunlight + H2O  ATP + NADPH + O2 Photosynthesis: 6CO2 + 6H2O  6O2 + C6H12O6