1. oxygen+ glucose carbon dioxide+ water +energy
Cellular Respiration
oxygen+ glucose carbon dioxide+ water +energy
6O2 + C6H12O6  6CO2 + 6H2O +ATP

2. Cellular Respiration
Since animals cannot create food they eat plants, or they eat plant-eating animals.
Plants and animals get energy from food by cellular respiration.
Occurs in the mitochondria, of the cell.
Oxygen is used to get the energy out of sugar.

3. Cellular Respiration How much energy is actually in food?
1 gram of the sugar glucose, when burned in the presence of oxygen, releases 3811 calories of heat energy!!!!
What is a calorie?
The amount of energy needed to raise the temp of one gram of water 1 degree Celcius.

4. Cellular Respiration
Cells, of course don’t burn glucose, instead they gradually release energy from glucose and other food compounds. Release of energy from glucose occurs in 3 steps
The pathway begins with Glycolysis
The Krebs Cycle
And the Electron Transport Chain

5. Glycolysis Occurs in the cytoplasm of the cell.
Glycolysis is the process in which one molecule of glucose(6C) is broken in half, producing two molecules of pyruvic acid(3C)
Requires 2 ATP molecules to get it started but produces 4 ATP molecules and 2 NADH molecules in return

6. The cell has a net gain of 2 ATP
Glycolysis
The cell has a net gain of 2 ATP

7. Fermentation
When Oxygen is not present, glycolysis is followed by a different pathway.
Fermentation.
Alcoholic Fermentation –
Produces Ethyl Alcohol and Carbon dioxide
Bread, beer, and wine are produced

8. Fermentation Lactic Acid Fermentation
Produced in your muscles during rapid exercise when the body cannot supply enough oxygen to the tissues. This is why muscles feel sore after intense activity
Produces Lactic Acid and NAD+

9. Without Oxygen= Anaerobic
Fermentation
Without Oxygen= Anaerobic

10. Overview of Cellular Respiration
Electrons carried in NADH
Electrons carried
in NADH and
FADH2
Pyruvic acid
Glucose
Glycolysis
Cytoplasm
Cellular respiration is the process that releases energy by breaking down food molecules in the presence of oxygen. Glycolysis takes place in the cytoplasm. The Krebs cycle and electron transport take place inside the mitochondria.
Mitochondrion
Copyright Pearson Prentice Hall

11. Cellular Respiration

12. Krebs Cycle Also called the citric acid cycle Occurs after glycolysis
Aerobic respiration (with oxygen)
Occurs in the mitochondria
During the Krebs Cycle, pyruvic acid is broken down into carbon dioxide, NADH, ATP, and FADH2 in a series of energy extracting reactions. 2

13. Krebs Cycle Steps:
In the presence of oxygen, pyruvic acid produced in glycolysis passes to the 2nd stage of cellular respiration. During the Krebs cycle, pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions.
Pyruvic Acid enters the mitochondrion, eventually forming citric acid.
Citric acid is broken down to form a 4-carbon molecule and carbon dioxide.
FADH2 and NADH are formed.

14. Figure 9-6 The Krebs Cycle

15. Chemical Pathways Glucose Glycolysis Electron Transport Krebs Cycle
Fermentation (without 0xygen)
Alcohol or lactic acid

16. Electron Transport Chain
Uses high-energy electrons from the Krebs cycle to convert ADP into ATP. High-energy electrons from NADH and FADH2 are passed into and along the electron transport chain. As H is released to form NAD and FAD, ATP is formed.
A TOTAL of 38 ATP are formed but 2ATP are used in Glycolysis leaving a net of 36 ATP.

17. Figure 9–7 Electron Transport Chain
Mitochondrion
Electron Transport
Hydrogen Ion Movement
Channel
Intermembrane
Space
ATP synthase
Inner
Membrane
Matrix
ATP Production
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18. Total energy produced by aerobic respiration = 36 ATP

19. Comparing Photosynthesis and Cellular Respiration
Function
Energy storage
Energy release
Location
Chloroplasts
Mitochondria
Reactants
CO2 and H2O
C6 H12O6 and O2
Products
C6H12O6 and O2
Equation
6CO2 +6H2O -> Glucose + 6O2
6O2 + Glucose -> 6CO2 +
6H2O