170 likes | 311 Vues
T he P rocess of P hotosynthesis. P hoto = L ight S ynthesis = T o M ake. Light energy is converted to chemical bond energy. With this energy the chemical bonds of carbon dioxide and water are broken and reassembled into carbohydrates. In this process oxygen is also produced.
E N D
Photo = LightSynthesis = To Make • Light energy is converted to chemical bond energy. With this energy the chemical bonds of carbon dioxide and water are broken and reassembled into carbohydrates. In this process oxygen is also produced.
Photosynthetic Organisms: Photoautotrphs • Cyanobacteria, algae, protists, as well as plant are all capable of conducting photosynthesis. • Most of the photosynthesis on Earth is carried out by phytoplankton
In Plants Photosynthesis Occurs In the Chloroplasts Within the Leaves
The Nature of Light Photons are discreet packets of light energy made in the sun that travel in waves of different lengths. Visible light is composed of wavelengths ranging from 380 to 750 nanometers. Photosynthetic pigments convert some of these visible light wavelengths into chemical energy. For Photosynthesis, light energy from the blue and red portions of the spectrum are converted to chemical bond energy.
Chloroplasts Have the Green Pigment Chlorophyll • Pigments absorb certain wavelengths of light and convert their energy into chemical energy. • Pigments reflect or transmit wavelengths of light energy that they do not convert to chemical energy, therefore, they appear this color. • Chlorophyll is green, therefore, it absorbs blue and red wavelengths of light
Redox Reactions • During photosynthesis light energy is converted to chemical energy which drives the redox reaction above. • Reduction occurs when atoms of molecules gain electrons and become more complex. • Oxidation occurs when atoms of molecules lose electrons and are simplified.
Photosynthesis/RespirationMatter Recycled, Energy Transformed • Photosynthesis: 6CO2 + 6H2O C6H12O6 + 6O2 • Respiration: C6H12O6 + O2 6CO2 + 6H2O Notice that the products of photosynthesis are the reactants of respiration and the products of respiration are the reactants of photosynthesis, in this way matter is recycled. Energy comes from the sun, it is transformed during photosynthesis to chemical energy in the bonds of food and then through cellular respiration into ATP.
Photosynthesis: Two Reactions: Light Dependent and Light Independent
Light Dependent Reaction During the light dependent reaction three main events occur as solar energy is transformed: 1. Water is split into hydrogen and oxygen (Photolysis). This is the source of atmospheric oxygen. 2. NADP+ is reduced to NADPH (with the H+ that comes from photolysis) 3. ADP + P → ATP (Photophosphorilation)
Calvin Cycle Is Light Independent • During the light independent reaction, ATP (formed during photophosphorilation) provides the energy to “fix” carbon dioxide (reduced it with hydrogen donated by NADPH formed in the light dependent reaction) to form carbohydrates.
Producers: Produce Food • Photoautotrophs produce “food” which is consumed directly or indirectly by organisms at all trophic levels of a food chain/ web.
Producers: Produce Oxygen • Photoautotrophs, produce oxygen through photolysis. • This oxygen becomes atmospheric oxygen gas • Ozone layer • Oxygen for aerobic cellular respiration
To Counteract the Greenhouse Effect:Plant a Tree Carbon Dioxide is one of the component gases of the “greenhouse” gas layer, which traps reradiated solar radiation near the surface of our planet and increases global warming. The more photosynthesis that takes place on our planet, the more carbon dioxide that is consumed in the photosynthetic process and the less carbon dioxide available to the greenhouse gas layer . PLANT A TREE TO COMBAT GLOBAL WARMING!!!
To Counteract Ozone Holes: Pant a Tree • The ozone layer in the stratosphere is made up of oxygen. • It shields the planet against the damaging effects of ultraviolet radiation and other forms of solar radiation which increase global warming. • Holes in the ozone layer caused by anthropogenic pollution can be patched up with atmospheric oxygen. • Increasing photosynthetic output will increase atmospheric oxygen and help to repair the ozone layer.
Human legacy is the sustainability of life on Earth G. Inguanzo Jr. Appalachian Blue Ridge Habersham County Georgia 2006