Photosynthesis and Cellular Respiration PDF

Photosynthesis and Cellular Respiration Prepared by: Eugene C. Pansaon, LPT ►Photosynthesis is the entire process of capturing light energy to produce food. ►Plants, algae, and other chlorophyll-bearing organisms capture light energy and use it to produce energy-rich organic molecu...

Photosynthesis and Cellular Respiration Prepared by: Eugene C. Pansaon, LPT ►Photosynthesis is the entire process of capturing light energy to produce food. ►Plants, algae, and other chlorophyll-bearing organisms capture light energy and use it to produce energy-rich organic molecules from carbon dioxide. Photosynthesis is summarized in the following equation. ► It consists of two sets of chemical reactions: the light-dependent reactions and the light- independent. ► During photosynthesis, plants carry out three vital energy conversions: 1. Conversion of light energy to electron energy. 2. Conversion of electron energy to short- energy storage (ATP). 3. Conversion of ATP to long-term energy storage (sugars). 1. Light-dependent Reactions ► This reaction can take place only in the presence of light (solar energy) light-dependent reactions are also known as energy-capturing reaction, they capture solar energy and store it in molecules that will supply the energy necessary for the next reactions to occur. ► Following are the steps: a.) Conversion of light energy to electron energy. b.) Splitting of water. c.) Conversion of electron energy into chemical energy in ATP. Light-independent Reaction ► They do not require light in order to take place. These reactions convert short-term energy storage (ATP) to long-term energy storage (sugar). ► The following are the steps: a.Carbon Dioxide Fixation - The reaction occurs when carbon dioxide enters the leaf. With the rid of an enzyme, RuBP carbonless (RuBisCo), carbon dioxide is attached to ribulose 1,5- biphosphate (RuBP), an organic compound containing 5-carbon atoms. b. Carbon Dioxide Reduction - The 6-carbon molecule splits into two molecules of phosphoglyceric acid (PGA). - Each in a series of chemical reactions are reduced to phosphoglyceraldehyde (PGAL) a molecule that can be converted to sugar. c. Glucose Formation - Two PGAL molecules have their atoms rearranged to form a 6-carbon sugar. Eventually, glucose is formed. LIGHT-DEPENDENT REACTION LIGHT-INDEPENDENT REACTION (CALVIN CYCLE) GLYCOLYSIS THANK YOU!