What results if glucose is metabolized under completely anaerobic conditions?

Under completely anaerobic conditions, glucose metabolism results in different end products depending on the type of anaerobic process or fermentation occurring. Here are the primary outcomes:

1. Alcoholic Fermentation:

• Organism: Yeast (e.g., Saccharomyces cerevisiae).
• Products: Ethanol (alcohol) and carbon dioxide.
• Overall Reaction: C6​H1​2O6​→2C2​H5​OH+2CO2​​
• Context: This process is used in brewing and baking, where ethanol is used to make alcoholic beverages, and carbon dioxide helps dough rise.

2. Lactic Acid Fermentation:

• Organism: Lactic acid bacteria (e.g., Lactobacillus species) and muscle cells in animals.
• Products: Lactic acid and ATP (energy).
• Overall Reaction: C6​H1​2O6​→2CH3​CHOHCOOH+2ATP
• Context: This process occurs in fermented dairy products (like yogurt and cheese) and in muscle cells during intense exercise when oxygen is scarce, leading to lactic acid buildup.

Summary

In both cases, glucose is partially oxidized to produce energy (ATP) and different byproducts. The exact byproducts depend on the type of fermentation: ethanol and carbon dioxide in alcoholic fermentation, or lactic acid in lactic acid fermentation.