1. Photosynthetic Adaptations and Fermentation Mr. Rogers and Mr. Gil AP Biology January 12, 2010

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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