After studying this chapter, you should be able to accomplish the following outcomes: List the types of organisms that carry on photosynthesis; identify the main pars of a chloroplast; show that photosynthesis is a redox reaction that produces a carbohydrate and releases O2;. | Photosynthesis Chapter 7 Photosynthesis Overview Energy for all life on Earth ultimately comes from photosynthesis. 6CO2 + 12H2O C6H12O6 + 6H2O + 6O2 Oxygenic photosynthesis is carried out by: cyanobacteria, 7 groups of algae, all land plants Photosynthesis Overview Photosynthesis is divided into: light-dependent reactions -capture energy from sunlight -make ATP and reduce NADP+ to NADPH carbon fixation reactions -use ATP and NADPH to synthesize organic molecules from CO2 Photosynthesis Overview Photosynthesis takes place in chloroplasts. thylakoid membrane – internal membrane arranged in flattened sacs -contain chlorophyll and other pigments grana – stacks of thylakoid membranes stroma – semiliquid substance surrounding thylakoid membranes Discovery of Photosynthesis The work of many scientists led to the discovery of how photosynthesis works. Jan Baptista van Helmont (1580-1644) Joseph Priestly (1733-1804) Jan Ingen-Housz (1730-1799) F. F. Blackman (1866-1947) Discovery of Photosynthesis C. B. van Niel, 1930’s -proposed a general formula: CO2+H2A + light energy CH2O + H2O + 2A where H2A is the electron donor -van Niel identified water as the source of the O2 released from photosynthesis -Robin Hill confirmed van Niel’s proposal that energy from the light reactions fuels carbon fixation Pigments photon: a particle of light -acts as a discrete bundle of energy -energy content of a photon is inversely proportional to the wavelength of the light photoelectric effect: removal of an electron from a molecule by light -occurs when photons transfer energy to electrons Pigments Pigments: molecules that absorb visible light Each pigment has a characteristic absorption spectrum, the range and efficiency of photons it is capable of absorbing. Pigments chlorophyll a – primary pigment in plants and cyanobacteria -absorbs violet-blue and red light chlorophyll b – secondary pigment absorbing light wavelengths that chlorophyll a does | Photosynthesis Chapter 7 Photosynthesis Overview Energy for all life on Earth ultimately comes from photosynthesis. 6CO2 + 12H2O C6H12O6 + 6H2O + 6O2 Oxygenic photosynthesis is carried out by: cyanobacteria, 7 groups of algae, all land plants Photosynthesis Overview Photosynthesis is divided into: light-dependent reactions -capture energy from sunlight -make ATP and reduce NADP+ to NADPH carbon fixation reactions -use ATP and NADPH to synthesize organic molecules from CO2 Photosynthesis Overview Photosynthesis takes place in chloroplasts. thylakoid membrane – internal membrane arranged in flattened sacs -contain chlorophyll and other pigments grana – stacks of thylakoid membranes stroma – semiliquid substance surrounding thylakoid membranes Discovery of Photosynthesis The work of many scientists led to the discovery of how photosynthesis works. Jan Baptista van Helmont (1580-1644) Joseph Priestly (1733-1804) Jan Ingen-Housz (1730-1799) F. F. Blackman .
