1. Cellular Respiration

2. Cellular Respiration
Cellular respiration releases chemical energy from sugars and other carbon-based molecules to make ATP.
It is an aerobic process.
needs oxygen to take place.

3. Cellular Respiration Cell respiration takes place in the mitochondria.
Foods are broken down into small molecules like glucose.
Glucose is broken down during glycolysis.

4. Glycolysis Glycolysis Takes place BEFORE cell respiration.
Splits the glucose molecule into two three-carbon molecules and makes two molecules of ATP.
It takes place in the cytoplasm of the cell.
It is an anaerobic process.
Does NOT require oxygen to take place.

5. Krebs Cycle The first part of cellular respiration.
Sometimes called the citric-acid cycle.
Produces molecules that carry energy to the second part of cellular respiration. (NADH and FADH2)
Takes place in the interior space (matrix) of the mitochondria.

6. Krebs Cycle 1. Pyruvate broken down.
Pyruvate is split into 3 molecules of carbon Dioxide which are given off as waste
4 molecules of NADH and one FADH2 form.
They will move to the electron transport chain.

7. Krebs Cycle Products
The Krebs cycle will break down TWO pyruvate molecules at the same time.
Products:
6 carbon dioxide molecules.
2 molecules of ATP
8 molecules of NADH
Will go to the electron transport chain.
2 molecules of FADH2

8. Electron Transport Chain
Second part of cellular respiration.
Energy from the Krebs cycle (NADH and FADH2) is transferred to a chain of proteins in the inner membrane of the mitochondrion.
A large number of ATP molecules are made.
Oxygen is used to make water molecules.
Water and heat are given off as a waste

9. Electron Transport Chain
1. Electrons removed.
Proteins inside the mitochondrion take high-energy electrons from NADH and FADH2.
Two molecules of NADH and one of FADH2 are used.
2. Hydrogen ions transported.
Hydrogen ions are built up along the inner mitochondrial membrane using energy from the electrons.

10. Electron Transport Chain

11. Electron Transport Chain Products
For EACH molecule of glucose the ETC can make:
Up to 34 molecules of ATP

12. Cellular Respiration Products
Up to 38 ATP are made from the breakdown of ONE glucose molecule.
2 ATP from glycolysis
36 ATP from cellular respiration (Krebs - 2) Cycle and Electron Transport Chain - 34)
Other products include carbon dioxide and water.
The equation for cellular respiration is:
C6H12O6 + 6O CO2 + 6H2O

13. Fermentation
Fermentation is an anaerobic process that takes place when there is less oxygen in the body (i.e. during strenuous activity)
Fermentation does NOT make ATP, but it allows glycolysis to continue.
Glycolysis needs NAD+ to pick up electrons when it splits glucose into pyruvate.
Fermentation removed electrons from NADH molecules and recycles NAD+ molecules for glycolysis.

14. Lactic Acid Fermentation in Animals
1. Pyruvate and NADH from glycolysis enter fermentation.
Two NADH molecules are used to convert pyruvate into lactic acid.
As the NADH is used, it converts back to NAD+.
2. TWO molecules of NAD+ are recycled back to glycolysis.
This allows your body to continue to break down sugar for energy!

15. Alcoholic Fermentation in Plants
1. Pyruvate and NADH from glycolysis enter alcoholic fermentation.
The NADH molecules provide energy to break pyruvate into alcohol and carbon dioxide.
As the NADH are used, they are converted to NAD+.
2. The molecules of NAD+ are recycled back to glycolysis.
The recycling of NAD+ allows glycolysis to continue.

16. Cellular Respiration and Photosynthesis
Cellular Respiration and Photosynthesis are approximately the reverse of each other.
Photosynthesis stores energy.
Cellular Respiration releases it.

17. Photosynthesis and Cellular Respiration