#4: Anaerobic Cellular Respiration

Question 1

Anaerobic Cellular Respiration

- when is it used, how?

Answer 1

Occurs in absence of oxygen, takes place in cytoplasm

Uses glycolysis to produce 2 ATP from glucose

In order to produce ATP, glycolysis must first reduce NAD+ to NADH
As result, needs continuous supply of NAD+ to produce ATP and pyruvate

Developed alternative means to oxidizing NADH in absence of oxygen to provide NAD+

Question 2

Aerobic vs Anaerobic

Answer 2

Under aerobic conditions, NAD + is continually supplied via the oxidation of NADH in the ETC

In the absence of oxygen the ETC cannot occur and consequently the ETC cannot be used to oxidize NADH
Fermentation used instead

Question 3

Ethanol Fermentation
(alcohol fermentation)
- location
- process
- products

Answer 3

occurs in plants, yeast, and some bacteria

Step 1 – pyruvate is converted into acetaldehyde
Step 2 – NADH is oxidized by converting acetaldehyde into ethanol

Final products - CO2 , ethanol, and two molecules of ATP

Question 4

Lactic Acids Fermentation 
(lactate fermentation)
- location 
- process
- products

Answer 4

occurs in animal cells

NADH is oxidized by converting pyruvate into lactic acid

Final products - lactic acid and two molecules of ATP

Question 5

Industries that rely on Ethanol Fermentation

Answer 5

Fermentation is used in food production

• Beer
• Wine
• Bread
• Olives/Pickles
• Vinegar

Question 6

Example of Lactic Acid in human bodies

Answer 6

For example, in muscle tissues during rapid and vigorous exercise, muscle cells may be depleted of oxygen. They then switch from respiration to fermentation.

Lactate produce transported from muscle to liver where oxidized back to pyruvate so does not build up in muscle tissue

Question 7

Creatine Phosphate Pathway

Answer 7

• Must have ATP readily available
• Aerobic Cellular Respiration takes time
  
  • Muscles, brain huge demand for ATP in bursts

Creatine + ATP = Creatine phosphate +ADP
(excess) (can be stored)

Reaction is easily reversible to generate ATP quickly

Creatine phosphate +ADP = Creatine + ATP