1. Anaerobic respiration
Fermentation
Anaerobic respiration

2. Anaerobic bacteria Use inorganic molecules as their electron acceptors
Nitrates
sulfate

3. Fermentation Pyruvate is reduced by NADH Alcohol and carbon dioxide OR
lactate

4. Alcoholic fermentation
Ex. Yeasts,
produce ethyl alcohol and CO2
Alcohol usually ends up killing the yeast.

7. Lactic Acid Fermentation
Ex. Animals, some bacteria and fungi
NADH reduces pyruvate to lactate
Muscle cells see this when oxygen is not delivered to the cells fast enough.
Bacteria produce cheese, yogurt, important chemicals (isopropanol, acetic acid)

9. Fermentation Advantages: Disadvantages:
2 ATP, use in certain animals in tissues
Disadvantages:
Toxic to cells, upon build up it can change the pH and cause muscle fatigue.
Oxygen debt – amount of O2 needed to rid body of lactate, lactate goes to liver where it is converted back to pyruvate.

10. Fermentation Efficiency Aerobic respiration = 39% effieciency
2 ATP = 14.6 kcal
Complete breakdown to CO2 and water - possible energy yield of 686 kcal
= 2.1%
Aerobic respiration = 39% effieciency

11. Fermentation Input: glucose and 2 ATP (glycolysis) 2 pyruvate 
2 lactate
2 alcohol and carbon dioxide and 2 ATP

12. Metabolic pool Degradative reactions  catabolism  exergonic
Ex. Glucose, fat, proteins can be used as energy sources as well and enter the metabolic pathway
Synthetic reactions Anabolism  endergonic
Compounds that enter the pathways are oxidized to substrates that can be used for biosynthesis