1. Cellular Energy
Cellular Respiration

2. Cellular Energy
Energy (from breaking down food) is trapped temporarily in ATP
Oxygen makes production of ATP more efficient
Aerobic (aero = with air) reaction
ATP is produced in the presence of oxygen
Sometimes ATP can be produced without oxygen
Anaerobic (an = not or non, aero = with air) reaction
ATP is produced WITHOUT the presence of oxygen

3. Cellular Respiration The two stages of cellular respiration are:
1. Glycolysis- Glucose (simple sugar) is broken down into 2 pyruvates and small amount ATP and NADH
2. Kreb’s Cycle- Pyruvate & NADH are used to make more ATP. Electrons are donated to make an even more ATP
C6H12O6 + 6O CO2+ 6H ATP

4. Glycolysis – Breaking Down Glucose
Glycolysis [glyco=carbohydrate (sugar), -lysis=to break)
1st stage of cellular respiration
Anaerobic process
Enzymes in mouths and stomachs break large carbohydrates (ex. Starch) into glucose
Glucose is used in the cytoplasm to fuel Glycolysis

5. Glycolysis Occurs in the cytoplasm of cells
Glucose is converted into pyruvate producing a small amount of ATP.
(Remember glucose is an energy source.)
If there is not enough glucose for glycolysis, then lipids can be used. (ex. fats = energy storage)
This is what happens when we diet.

6. Cellular Respiration Under Aerobic Conditions
Aerobic Respiration
Krebs Cycle:
Occurs in mitochondria
-Pyruvate produced by glycolysis enters a mitochondria & gets converted to Acetyl-CoA
-Acetyl-CoA starts Krebs cycle to produce ATP & NADH.

7. Cellular Respiration Under Anaerobic Conditions
If oxygen is not available for respiration, fermentation occurs
Fermentation- recycling of energy (as NAD+) without the presence of oxygen
Krebs cycle can’t happen
Two types of Fermentation:
Lactic Acid
Alcohol

8. Fermentation: Lactic Acid
Lactic Acid Fermentation
During glycolysis pyruvate is converted to Lactic Acid instead of Acetyl-CoA
This lactic acid can build up in muscle cells causing muscle soreness

9. Fermentation: Alcohol Fermentation
Alcoholic Fermentation
During glycolysis pyruvate is converted to ethanol (alcohol)
Yeast releases ethanol and carbon dioxide as waste during fermentation
The carbon dioxide causes bread to rise and carbonation of beer
Ethanol causes the intoxicating effects of alcoholic beverages.

10. Electron Transport Chain: Review
During AEROBIC respiration energy donated by the Krebs cycle fuels the electron transport chain (ETC)
For a small amount of energy put into the chain, the ETC produces a massive amount of ATP.

11. Cellular Respiration Wrap-Up

12. Photosynthesis vs. Respiration
The products for photosynthesis are the materials for cellular respiration and visa versa
Photosynthesis starts of with carbon dioxide, water and energy and ends with the production of sugar and water
Cellular respiration starts of with sugar and oxygen and ends with the production of carbon dioxide, water and energy.
Is stored
Is Harvested