(3412) 21.Biotechnology & Genetic Modification(Part 1)(Cambridge IGCSE Biology 0610 for 2023, 2024 & 2025)

Introduction to Biotechnology and Genetic Modification

• Biotechnology: Utilizing living organisms (like bacteria or cells) to create products or address issues.

  • Example: Yeast in bread-making produces carbon dioxide for dough's rise.

• Genetic Modification: Altering the DNA of organisms (plants or animals) to exhibit specific traits.

  • Example: Modifying rice to increase Vitamin A for health improvements in regions with deficiencies.

The Role of Bacteria in Biotechnology

• Common Microorganisms: Bacteria are frequently used in biotechnology due to:

  • Rapid reproduction rates.

  • Ability to synthesize complex molecules.

  • Limited ethical concerns: Simple organisms with controlled genetic manipulation.

  • Plasmids: Small DNA circles that allow easy genetic modifications.

Biotechnology Products

• Examples of Products:

  • Biofuels

  • Bread

  • Fruit juice

  • Biological washing powders

  • Lactose-free milk

  • Insulin

  • Penicillin

  • Mycoprotein

Anaerobic Respiration in Yeast

• Anaerobic Respiration: Yeast converts sugar (glucose) to ethanol and carbon dioxide without oxygen.

  • Equation: C6H12O6 (glucose) → 2 C2H5OH (ethanol) + 2 CO2 (carbon dioxide) + Energy

  • Importance: Produces products like ethanol (biofuel) and carbon dioxide (bread rising).

Biofuels

• Definition of Biofuels: Fuels produced from organic materials (plants or waste).

  • Environmental Benefits: Renewable source, fewer harmful emissions.

  • Creation: Plants with sugar mixed with yeast, where yeast ferments it into ethanol.

Bread Production

• Process: Yeast is combined with sugar, flour, and water; anaerobic respiration generates carbon dioxide that makes the dough rise, resulting in an airy texture.

Fruit Juice Production

• Pectin: A plant cell wall protein that gives fruits thickness and challenges juice extraction.

• Role of Pectinase: Enzyme that breaks down pectin, facilitating juice extraction from fruit.

Biological Washing Powders

• Enzymes in Washing Powders: Biological enzymes target specific stains:

  • Protease: Breaks down protein stains (e.g. egg, blood).

  • Lipase: Targets grease or oil stains.

• Benefits: Effective at lower temperatures; energy conservation by reducing hot water needs.

Lactose-Free Milk

• Lactose: Natural sugar in milk, problematic for lactose-intolerant individuals.

  • Lactase Enzyme: Added to milk to break down lactose into more digestible sugars.

  • Visual Aid: Diagram depicting lactose breakdown for better understanding.

Understanding Fermenters

• Definition: Large containers for growing bacteria or fungi to produce valuable products.

• Controlled Environment: Ensures optimal conditions for microorganism growth for large-scale production.

Products from Fermenters

• Insulin: Produced by bacteria; essential for diabetes management.

• Penicillin: An antibiotic made from the fungus Penicillium, vital in treating infections.

• Mycoprotein: Protein source from fungi used as a meat alternative.

Controlling Conditions in Fermenters

• Key Factors:

  • Temperature: Crucial for enzyme reactions; extremes can harm organisms.

  • pH Levels: Different microorganisms prefer specific pH; must be managed for optimal growth.

  • Oxygen Levels: Varies by microbe; needs regulation for successful metabolization.

  • Nutrient Supply: Essential for microbial growth; requires careful management.

  • Waste Management: Removal of waste is necessary to prevent growth inhibition.

Conclusion

• This concludes part 1 of Chapter 21: Biotechnology and Genetic Modification.

• Encouragement to provide feedback and subscribe for more educational content.