1. Cellular Respiration
Chapter 9-1

3. Cellular Respiration Aerobic
The process in which cells make ATP by breaking down organic compounds, like glucose in the presence of oxygen.
SUNLIGHT
PHOTOSYNTHESIS
C6H12O6 + 6O2
6CO2 + 6H2O
AEROBIC RESPIRATION

4. start (glycolysis) in cytoplasm
A biochemical pathway in which glucose is used to produce pyruvic acid in the cytoplasm just outside the mitochondria.
start (glycolysis) in cytoplasm
completed in mitochondrion

5. - Step #1
Glucose is split into two, 3-carbon molecules of PGAL, using a couple ATP’s and NADH.

6. Step #2
During this step energy from PGAL is passed to an electron acceptor called NAD, forming NADH.

7. Step #3
More ATP’s are made.

8. Eventually Pyruvic acids and 2 ATP’s are produced.
Step #4
Eventually Pyruvic acids and 2 ATP’s are produced.

9. PGAL
Made at the beginning of Glycolysis and is converted into 2 molecules of Pyruvic Acid.

10. Products of Glycolysis
Small amounts of ATP
2 molecules of Pyruvic Acid
NADH
ATP

12. Conclusion and Glycolysis Chart
Location – Cytosol just outside the mitochondria
Function – Breaking down glucose to Pyruvic Acid
Reactants – Glucose ADP and NAD (accepts high energy electrons)
Products – ATP, NADH, Pyruvic
Acid.

13. Fermentation - Cytosol ( without oxygen) Anaerobic Respiration
Process: pyruvic acid (initial reactant )produced from glycolysis is converted to other organic compounds.
Fermentation does not produce ATP but does regenerate NAD+ which keeps glycolysis going.

14. Pathways of Fermentation
Two main pathways: lactic acid fermentation and alcoholic fermentation

15. Lactic Acid Fermentation
1. An enzyme converts pyruvic acid into a 3-C molecule called lactic acid (stored in your muscles – Soreness)
2. During fermentation, NADH is converted into NAD. No ATP is made.

16. 3 NAD will now recycle back to glycolysis to help break down glucose to produce pyruvic acid.
4. Regenerating NAD in fermentation ensures the cycle of glycolysis to continue operating.
5. No ATP is made in this fermentation.
NADH – Made in glycolysis and broken down into NAD in fermentation.

17. electrons, hydrogen from NADH
GLYCOLYSIS
C6H12O6 2
ATP
energy input
2 ADP
2 NAD+ 2
NADH 4
ATP
2 pyruvate
energy output
2 ATP net
LACTATE FORMATION
electrons, hydrogen from NADH
2 lactate
Fig. 7.9, p. 118

18. Alcoholic Fermentation
An enzyme converts pyruvic acid into ethyl alcohol in two steps:
Step -1. A CO2 molecule is removed from the pyruvic acid, leaving a 2-C molecule

19. Step 2: Two hydrogen atoms from NADH are added to the 2 - carbon compound to form ethyl alcohol,
a. recycling NAD to return to Glycolysis.

20. Products
Process results in the making of beer, wine, and bread.

21. electrons, hydrogen from NADH
GLYCOLYSIS
C6H12O6 2
ATP
energy input
2 ADP
2 NAD+ 2
NADH 4
ATP
energy output
2 pyruvate
2 ATP net
ETHANOL FORMATION
2 H2O
2 CO2
2 acetaldehyde
electrons, hydrogen from NADH
Fig. 7.10, p. 119
2 ethanol

22. Conclusion and Alcoholic Fermentation and Lactic acid Chart
Location – Cytosol
Function – Recycle NAD for glycolysis
Reactants – Pyruvic Acid and NADH
Alcohol Products - – Alcohol, Carbon Dioxide, NAD
Lactic acid Products – Lactic acid and NAD