1. Fermentation

2. Cellular Respiration
The respiration that we’ve discussed to this point has all relied on oxygen
There are several types of respiration that can occur without oxygen
These methods still rely on glycolysis to produce ATP, but create different waste products

3. What if oxygen is missing?
No oxygen available = can’t complete aerobic respiration
Cells can undergo:
Anaerobic respiration
(also known as fermentation)
2 Types:
alcohol fermentation
lactic acid fermentation
no oxygen or no mitochondria necessary
(think bacteria)
can only make very little ATP
large animals cannot survive long term using fermentation
yeast
bacteria

4. Anaerobic Respiration
lactic acid fermentation
bacteria, animals
bacteria make yogurt
animals feel muscle fatigue
glucose  ATP + lactic acid

5. Lactic acid fermentation
Glucose->pyruvic acid -> 2ATP lactic acid
GLYCOLYSIS FERMENTATION
used to make cheese and yogurt
~ in humans during strenuous exercise
not enough oxygen from blood “oxygen debt”
~ lactic acid accumulates in muscle; leads to fatigue and pain
Will be converted back to pyruvic acid in liver

6. Anaerobic Respiration
alcohol fermentation
yeast
make beer, wine, bread
glucose  ATP + CO2+ alcohol O2

7. Alcoholic fermentation
glucose -> pyruvic acid-> ethyl alcohol + 2 CO2
2ATP
GLYCOLYSIS FERMENTATION
used by yeast cells and
some bacteria to produce
ATP, CO2 and ethyl alcohol