1. Chapter 7 - Cellular Respiration
Section 7-1 Glycolysis & Fermentation

2. Intro Video - 40 min
Fill in notes
15 ? Quiz after

3. Objective 1: Define cellular respiration
Process of breaking down organic compounds (mainly glucose) to release energy (ATP)
Cytosol
Cytosol

4. C6H12O6 + 6O2  6CO2 + 6H2O + Energy (ATP)
Cytosol
Cytosol

5. Objective 2: Describe the major events in glycolysis
Starts with glycolysis - the 1st step in cellular respiration
- glucose  pyruvic acid (energy) – occurs in cytosol

6. (see 7-1 ARG)
Each glucose  2 ATP (energy), 2 NADH (energy), & 2 pyruvic acid
Net 2 ATP b/c 2 used in step 1
Pyruvic acid takes 1 of 2 pathways:

7. http://highered. mcgraw-hill

8. 1. anaerobic pathways
> absence of oxygen
yield no additional ATP
use by many unicellular, some multicellular
> ex. Fermentation

9. 2. aerobic respiration
> oxygen is present
> produces considerable amount of ATP

10. Objective 3: Compare and contrast lactic acid fermentation and alcoholic fermentation (p.129)
both are processes that…
follow glycolysis, so use pyruvic acid
occur w/ little or no oxygen (O2)
produce no ATP
regenerate NAD+ (electron acceptor) for step 3 of glycolysis

11. Contrasts: lactic acid alcoholic muscle cells, fungi, & bacteria
Type of cells
muscle cells, fungi, & bacteria
plant cells and fungi (yeast)
Products
3-C lactic acid
2-C ethyl alcohol
By-products
leads to muscle fatigue/pain
releases CO2
Uses
used to make yogurt & cheese
used to make wine, beer, bread

12. Objective 4: Calculate the efficiency of glycolysis (p. 131)
kilocalorie (kcal) – unit of energy measurement; = 1,000 calories
It takes 12 kcals to make each ATP molecule

13. In glycolysis, ____ ATP are produced; this requires ____ kcals
The oxidation of glucose releases 686 kcals

14. Efficiency of glycolysis =
Energy required to make ATP
Energy released by oxidation of glucose
= ________ = _____ %

15. Efficiency of glycolysis =
Energy required to make ATP
Energy released by oxidation of glucose
2 X 12 = .035 = 3.5%
686 kcal

16. 7.2 Aerobic Respiration

17. Section 7-2 Aerobic Respiration
2 major stages, after glycolysis
Krebs Cycle
Electron Transport Chain (ETC)

18. Objective 5: Summarize the events of the Krebs cycle (see ARG 7-2)
What happens between glycolysis and the Krebs cycle?
Pyruvic acid:
1) enters matrix (space inside inner membrane)
2) reacts w/ CoA to form acetyl CoA
3) other carbon is released as carbon dioxide gas, CO2

19. Objective 6: Summarize the events of the electron transport chain (ETC)

20. - NADH and FADH2 (from Krebs cycle) provide electrons

21. - electron energy pumps hydrogen ions (H+) out of matrix & lose energy
> builds up H+’s between 2 membranes

22. - H+’s diffuse back into matrix through membrane protein, ATP synthase
> energy used to make up to 34 ATP from ADP & P; process called chemiosmosis

23. - final electron acceptor is oxygen, which also accepts protons (H+); forms water

24. Aerobic Respiration

26. Objective 7: Relate aerobic respiration to the structure of a mitochondrion
- Matrix contains enzymes that catalyze rxns. of Krebs cycle
- inner folded membrane has large surface area for ETC – Prokayotes in cell membrane

27. - proteins in inner membrane used as:
1) pumps to move H+’s & NADH (uses 2 ATP) out of inside the inner membrane
2) enzymes that catalyze chemiosmosis

28. Objective 8: Calculate the efficiency of aerobic respiration
36 ATP x 12 kcals = 432 kcals/686 kcals = = 63%, nearly 20 times more efficient than anaerobic respiration
63/3.5 = 18