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Photosynthetic Adaptations and Fermentation. Mr. Rogers and Mr. Gil AP Biology January 12, 2010. Normal Photosynthesis. In the Calvin cycle, CO2 is fixed to make a 3 carbon molecule by RuBP Autotrophs that do this are called C3 plants. Photosynthetic Adaptations. C4 plants and CAM plants
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Photosynthetic Adaptations and Fermentation Mr. Rogers and Mr. Gil AP Biology January 12, 2010
Normal Photosynthesis • In the Calvin cycle, CO2 is fixed to make a 3 carbon molecule by RuBP • Autotrophs that do this are called C3 plants
Photosynthetic Adaptations • C4 plants and CAM plants • C4 plants are found mainly in tropical areas or are crops like corn and sugarcane • CAM plants are “succulents” such as pineapple, aloe, and cacti • These plants are adapted to hotter, dryer regions • They alter the way materials are prepared going into the Calvin cycle
C4 Plants • Make a 4 carbon molecule when they fix carbon • C3 plants make a 3 carbon molecule • This occurs in the cytoplasm • Uses a compound called PEP to help make the 4 carbon molecule • Have a special kind of cell called the bundle-sheath cells
CAM Plants • CAM plants keep their stomata closed during the daytime • They open at night and convert the CO2 into acids, which are then stored • During the day, when there is light to do the light reactions and make NADPH and ATP, CO2 is released from the acids so photosynthesis can keep going
What happens if you aren’t getting enough oxygen to your cells? • Fermentation = making ATP without using oxygen • Occurs when your lungs and bloodstream can’t supply enough oxygen to your cells • Does not make as much ATP as cellular respiration (not efficient) • Anaerobic conditions
Why do your muscles hurt after exercise? • When you can’t keep up your oxygen levels, fermentation makes lactic acid • Lactic acid build up is what causes your muscles to be sore • It takes time to get rid of this lactic acid
How does fermentation work? • Need pyruvate (the product of glycolysis) • Use pyruvate to regenerate NAD+ • Makes 2 ATP per molecule of glucose • 2 Types: • Alcoholic = ethanol and carbon dioxide • Occurs in yeast • Lactic acid = lactic acid • Occurs in muscles