Fermentation

Question 1

Fermentation

Answer 1

• Fermentation breaks down glucose in the absence of oxygen
• It’s the process of reducing pyruvate to either ethanol or lactact to generate NAD+ from NADH.
• Fermentation uses pyruvate as the acceptor of high energy electrons from NADH
• NAD+ produced by reducing pyruvate ANAEROBICALLY is available for re-use in the glycolytic pathway so that more ATP can be created
• Under anaerobic conditions, each glucose molecule can generate one ATP molecule.

Question 2

Alcohol Fermentation

Step 1

Step 2

Answer 2

Step 1: removing a carboxyl group (decarboxylation) from pyruvate that produces acetaldehyde

Step 2: NADH passing its electrons to acetaldehyde (reduction of acetaldehyde) which regenerates NAD+ & froms ethanol

(alcohol dehydrogenase is the enzyme that converts acetaldehyde to ethanol)

fermentation in yeast generates ethanol

Question 3

Lactic Acid Fermentation

Answer 3

-mammals (eukaryotes)

• uses lactic acid to regenerate NAD+
• Lactate dehydrogenase is the enzyme that catalyzes this process converting pyruvate to lactate.

Question 4

The net equation of alcohol fermentation is:

Answer 4

Glucose + 2ADP + 2Pi + 2H+ → 2 ethanol + 2ATP + 2H2O + 2CO2

Question 5

The net equation of lactic acid fermentation is:

Answer 5

Glucose + 2ADP + 2Pi → 2 lactate + 2ATP + 2H2O