Anaerobic Respiration

1
Anaerobic Respiration

• Fermentation

2
Remember

• After glycolysis the next stages in cellular
  respiration are dependent on whether or not there
  is oxygen present

3
After glycolysis

• In the absence of oxygen some cells can convert
  pyruvic acid into other compounds through the
  biochemical pathways known as FERMENTATION.

4
Things to remember about these anaerobic pathways

• The additional fermentation pathways do NOT
  produce ATP.
• It does make NAD which is used to run glycolysis.

GLYCOLYSIS
ATP
NAD
5
TWO types of FERMENTATION

• Lactic acid fermentation
• Alcoholic fermentation

6
Lactic Acid Fermentation

• An enzyme converts pyruvic acid (made in
  glycolysis) to LACTIC ACID.
• This occurs in your muscle cells during very
  strenuous exercise.

7
Lactic Acid Fermentation

• During exercise muscle cells use up oxygen more
  rapidly than it can be delivered, and the body
  switches to lactic acid fermentation.
• The build up of lactic acid causes muscle cramps.

8
Alcoholic Fermentation

• Occurs in plant cells and unicellular organisms,
  like yeast, where pyruvic acid (made in
  glycolysis) is converted to ETHYL ALCOHOL.

9
Alcoholic Fermentation

• It is the CO2 produced by yeast during alcoholic
  fermentation that causes bread to rise
• It forms bubbles inside the dough, and the ethyl
  alcohol evaporates during baking.