1. Chapter 9: Cellular Respiration & Fermentation
life processes of all organisms require energy
energy held in bonds of food can’t be used directly by the cell
energy from food must be converted to the ONLY energy source that cells can use:
ATP!

3. Cellular Energy
oxygen in the air you breathe makes the production of ATP more efficient BUT some ATP is made without oxygen
processes that require oxygen are called aerobic
processes that do not require oxygen are called anaerobic

4. cellular respiration is the process where the energy in the bonds of nutrients (food!) are used to make ATP
respiration occurs continuously in ALL cells of ALL organisms – plants and animals
C6H12O O2  6 CO H2O + E
oxygen
carbon dioxide
water
ATP!
glucose

5. Stage 1: Glycolysis
takes place in the cytoplasm
anaerobic (doesn’t use oxygen)
glucose splits into pyruvic acid
also produces NADH and ATP

6. when oxygen is present, pyruvic acid produced during glycolysis enters a mitochondria
aerobic respiration begins!

7. Mitochondria Organelle where aerobic respiration takes place.
matrix
folded inner
membrane

8. aerobic pathway – inside mitochondria
Stage 2: Kreb’s cycle converts pyruvic acid into carbon dioxide (CO2) & produces 2 more ATP
Krebs Cycle also produces NADH (an electron carrier)

9. Stage 3: electron transport chain uses electrons (from NADH) and oxygen to produce 32 more ATP
water also produced

10. Energy Totals for Aerobic Respiration
aerobic respiration (with oxygen!) results in the production of 36 ATP molecules for each glucose molecule

11. anaerobic pathway – in the cytoplasm
when oxygen is not present, electrons carried by NADH are transferred back to the pyruvic acid produced during glycolysis
called fermentation
forms lactic acid (animals, bacteria) or alcohol (plants, yeast)

12. lactic acid fermentation
happens in animal muscle cells when they run out of oxygen
happens in bacteria to make yogurt, cheese, dill pickles

13. alcohol fermentation
happens in yeast to make beer, wine, bread

14. Energy and Exercise
for short, quick bursts of energy, the body uses ATP already in muscles
for exercise longer than about 90 seconds, cellular respiration is the only way to continue generating a supply of ATP