CIE IGCSE Biology: 复习笔记:20.1.7 Reasons for Conservation: Extended

CIE IGCSE Biology: 复习笔记:20.1.7 Reasons for Conservation: Extended

Reasons for Conservation: Extended

  • There are numerous reasons why conservation programmes are important
    • Maintaining or increasing biodiversity
      • Which allows ecosystems to remain stable
    • Reducing extinction
      • Helps to retain iconic species and maintain biodiversity
    • Protecting vulnerable ecosystems which would have been quickly lost to human activity
    • Maintaining ecosystem functions
      • Nutrient cycling eg. carbon cycling to hold back climate change
      • Resource provision, such as
        • Food - making sure we have enough for the population
        • Drugs - having access to plants for plant-based remedies
        • Fuel - for improtant activities such as cooking
        • Genes - so the gene pool remains wide and variety exists in all species

Conservation Techniques: Extended

  • Certain conservation techniques can be used to maintain biodiversity
  • Examples include
    • Artificial insemination (AI) in captive breeding programmes
      • This allows large numbers of offspring to be produced without the need for conventional sexual intercourse between males and females
    • In vitro fertilisation (IVF) in captive breeding programmes
      • This allows gametes with known alleles to be used in ensuring the next generation remains biodiverse

Risks to a species

  • If its population size decreases, a species will experience reduced genetic variation
  • This renders the species more susceptible to environmental change
  • The species is less resilient and has a greater risk of extinction