1. 1 Review Why do all organisms need food Relate Cause and Effect Why do macromolecules differ in the amount of energy they contain 2 Apply Concepts How does the process of cellular respiration maintain homeostasis at the cellular level Use Analogies How is the chemical energy in glucose similar to money in a savings account

2. Ch 9 Cellular Respiration and Fermentation

3. Chemical Energy and Food
Why do you need food
It provides the chemical building blocks they need to grow and reproduce
It contains chemical energy that is released when its chemical bonds are broken.

4. Calorie
Amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius
1000 calories = 1 kilocalorie, or Calorie.

5. Cellular Respiration
Series of chemical reactions that breaks down sugar and releases energy
Occurs in all living cells
Opposite of photosynthesis
Oxygen + Glucose  Carbon dioxide + Water + Energy
6 O2 + C6H12O6  6 CO2 + 6 H2O + Energy.

6. Cellular Respiration This occurs in animals AND plants
This is the process that whenever your body needs energy
In addition to sugar, fats and proteins may also be used.

7. Cellular Respiration release energy a little at a time Controlled
SIMILAR
DIFFERENT
Cellular Respiration release energy a little at a time
Controlled
Burn fuel
Produce heat
Produce H2O
Produce CO2
Produce energy

8. Stages of Cellular Respiration
Glycolysis
Krebs cycle
Electron Transport Chain (ETC).

9. Glycolysis Produces only a small amount of energy
Most energy (90%) remains in the chemical bonds.

10. Krebs Cycle
Produces only a small amount of energy.

11. Electron Transport Chain (ETC)
Produces the bulk of the energy
Uses oxygen.

12. Aerobic
Require oxygen
Krebb Cycle and ETC
Occurs in the mitochondria.

13. Anaerobic
Does not need oxygen
Glycolysis
Occurs in cytoplasm.

14. Photosynthesis and Cellular Respiration
Opposite processes
Photosynthesis “deposits” energy
Cellular respiration “withdraws” energy.

15. Glycolysis First stage of cellular respiration
Glucose is broken down into 2 molecules of the 3-carbon molecule pyruvic acid
ATP and NADH are produced.

16. Krebs Cycle Pyruvic acid is broken down into carbon dioxide
A.k.a. Citric Acid Cycle
ATP is produced.

17. Electron Transport
NADH and FADH2 pass their electrons to ETC.

18. Electron Transport
Electrons combine with H+ ions and oxygen to form water at end of ETC.

19. Electron Transport
The high energy electrons move H+ ions against a concentration gradient across the inner mitochondrial.

20. Electron Transport
H+ ions pass back through the ATP synthase causing it to spin
ATP synthase attaches a phosphate to ADP to produce ATP with each rotation.

21. Energy Totals
Complete breakdown of glucose through cellular respiration results in the production of 36 ATP molecules
The rest of the energy is “lost” as heat (64%).

22. Fermentation
Process of releasing energy from food in the absence of oxygen.

23. Fermentation NADH is converted back to NAD+
Allows glycolysis to continue producing ATP.

24. Alcoholic Fermentation
Pyruvic acid + NADH  Alcohol + CO2 + NAD+
Yeast and other microorganisms
Produces alcoholic beverages and causes bread dough to rise.

25. Lactic Acid Fermentation
Pyruvic acid + NADH  Lactic acid + NAD+
Humans and most organisms.

26. Quick Energy
Cells have enough ATP for a few seconds of intense activity
Lactic acid fermentation can supply enough ATP to last about 90 seconds
Extra oxygen is required to get rid of the lactic acid produced.

27. Long-Term Energy
Cellular respiration is required to continue production of ATP for exercise longer than 90 seconds
Body uses glycogen stores for the first minutes
Body then will break down other stored molecules, including fats.