Fermentation

A continuation of Glycolysis

Glycolysis

• Label the steps of glycolysis you learned about yesterday

GLUCOSE2 Pyruvic AcidMolecules

2NADH

Anaerobic Respiration:Fermentation

• Fermentation begins with pyruvic acid formed from glycolysis if no oxygen is present.

• Two types of fermentation can depending on the type of organism

Pyruvic Acid

Alcoholic Fermentation occurs in yeasts (fungus) and bacteria

Lactic Acid Fermentation occurs in animals’ muscle tissue

Alcoholic Fermentation• Pyruvic acid combines with one of the high energy

NADH molecules formed from glycolysis• Ethyl alcohol, carbon dioxide and NAD+ are formed • The NAD+ is reused in glycolysis • The ethyl alcohol and CO2 have some uses to humans

Pyruvic Acid

NADHEthyl

Alcohol

CO2 NAD+

Brewing Beer• Beer has been created by humans for over 10,000

years. • The CO2 produced makes the beer slightly

carbonated

Making Bread• As the yeast in bread dough produces CO2 the

it rises.• The alcohol is present in the raw dough but

evaporates away as the bread is baked

Lactic Acid Fermentation

• Pyruvic acid is converted into lactic acid by using a NADH molecule created during glycolysis.

Pyruvic Acid

NADHLactic Acid

NAD+

Feel the Burn!• Strenuous exercise causes

muscles to run low on oxygen so your cells switch to anaerobic respiration and produce lactic acid through fermentation.

• The buildup causes a burning sensation in your muscles