HKDSE Biology - Anaerobic respiration

• Outline the major steps of anaerobic pathways.
• Be aware of the occurrence of anaerobic respiration during exercise.

• Distinguish between aerobic and anaerobic respiration.

Anaerobic respiration ➡️Respiration that oxygen is not consumed to break down glucose.

👆🏻This photo showing the formation of lactic acid in muscle cell.

• After glycolysis, NADH transferring its electron to pyruvate and generating lactate.
• Lactate 👉🏻the deprotonated form of lactic acid.
• When too little oxygen for aerobic respiration to be carried out, then anaerobic respiration - lactic acid fermentation will be be carried out.
• The soreness after exercise is caused by the accumulation of lactic acid in muscle.
•  Lactic acid in muscle will convert back to pyruvate in liver.

👆🏻This photo showing the formation of ethanol and carbon dioxide in yeast.

• After glycolysis, the removal of the carboxyl group from pyruvate and generate acetaldehyde. 
• NADH transferring its electron to acetaldehyde and generate ethanol.
• Ethanol is utilized to make beer and wine.

1. Place of occurrence 

• Aerobic respiration - cytoplasm and mitochondria.
• Anaerobic respiration - cytoplasm.

2. Quantity of energy

• Aerobic respiration - high amount of energy with 38 ATP.
• Anaerobic respiration - low amount of energy with 2 ATP.

3. Final product 

• Aerobic respiration - carbon dioxide and water.
• Anaerobic respiration - lactic acid/ethanol and carbon dioxide.

4. Steps involved

•  Aerobic respiration - glycolysis, Krebs cycle and oxidative phosphorylation.
• Anaerobic respiration - glycolysis and fermentation.

5. Process of combustion 

• Aerobic respiration - complete.
• Anaerobic respiration - incomplete.

6. Duration of process

• Aerobic respiration - long process.
• Anaerobic respiration - relatively fast process.

Written by Bella | HKDSE Biology Specialist @ TUTTEE

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References

1. Khan Academy. Fermentation and anaerobic respiration | Cellular respiration (article). Khan Academy. https://www.khanacademy.org/science/biology/cellular-respiration-and-fermentation/variations-on-cellular-respiration/a/fermentation-and-anaerobic-respiration.
2. C, R., Arif, N., Annie, & Mahmooda. (2019, May 14). Difference Between Aerobic and Anaerobic Respiration (with Comparison Chart). Bio Differences. https://biodifferences.com/difference-between-aerobic-and-anaerobic-respiration.html.