Topic 1 - Classification and Biodiversity

• The classification system is based on the evolutionary relationships between organisms.
• It also allows scientists to communicate about different species using common names that everyone understands.
• Classification helps us to understand how species are related, which can be useful when studying their characteristics or behaviours.
• Plants


  • Flowering plants
  • Non-flowering plants
• Animals


  • Vertebrates
  • Invertebrates
• Morphological adaptations


  The features that an organism has to enable them to survive in their environment e.g. fur, large ears etc
• Behavioural adaptations


  What an organism does to enable it survive in their environment e.g. hibernation
• Things organisms compete for in their environment


  • Food
  • Water
  • Light
  • Minerals
• Factors that may affect population numbers


  • Predators
  • Competition for resources
  • Disease
  • Pollution
• Interspecific competition


  Competition between different species
• Intraspecific competition


  Competition between members of the same species
• A large sample size is needed because there will be a greater chance that you will have the true value that needs to be estimated
• When using capture-recapture technique to estimate a sample size, assumptions are made of no death, no immigration, no emigration, and the marking technique does not affect chances of survival
• Biological control agents


  A non-chemical way to control the numbers of unwanted organisms
• Advantages of biological control agents


  • No chemicals are used so there's less pollution, disruption of the food chain and risk to people eating the food that has been sprayed
  • There's no need to keep repeating the treatment like you would with chemical pesticides
• Disadvantages of biological control agents


  • The predator you introduce may not eat the pest
  • The predator could eat a useful species
  • The predators population may increase and get out of control
  • The predator may not stay in the area where it is needed
• Classification


  Putting things into groups
• What classification helps us understand


  • Variety of living things
  • How they changed over time
  • How they're related to each other through evolution
• Living organisms


  • Plants
  • Animals
• Plants


  • Flowering plants (produce flowers)
  • Non-flowering plants (ferns, mosses, etc)
• Animals


  • Vertebrates (have backbone)
  • Non-vertebrates (eg insects)
• Five kingdom classification


  Uses morphological features (structure or appearance)
• Five kingdom classification


  • Bacteria
  • Plants
  • Fungi
  • Single-celled organisms
  • Animals
• Classification groups


  • Domain
  • Kingdom
  • Phylum
  • Class
  • Order
  • Family
  • Genus
  • Species
• Scientific names


  To aid its identification and classification
• Binomial system


  Two-part Latin name used by biologists
• First name of organisms

  Genus, which the organism share with other closely related organisms
• Second name of organisms


  Species, no other organism in the genus has this name
• Advantages of Latin name


  • Name is the same worldwide and in all languages
  • No confusion or duplication that is caused by common names which are based on appearances which can be misleading
• Morphological adaptations


  • Ear length
  • Coat colour
  • Body mass
  • Thick fur
• Ear length adaptation


  • Small ears lose less heat, smaller surface area
  • Big ears lose more heat, larger surface area
• Coat colour adaptation


  • White is camouflage against predators/prey in snow
  • Sandy is camouflage against predators/prey in desert
• Body mass adaptation


  • Less heat is lost through surface of animal with large body mass
  • More heat is lose through surface of animal with small body mass
• Thick fur adaptation


  Keeping warm by trapping air as insulation, less heat loss
• Behavioural adaptations


  • Nocturnal
  • Migration
  • Hibernation
  • Living in groups
• Nocturnal adaptation


  Avoid heat of desert during day, hunt at night as it's cooler
• Migration adaptation


  Moving from one area to another when weather changes
• Hibernation adaptation


  Animals hibernate during cold temperatures
• Living in groups adaptation

  Protection against predators
• Population size


  How many of one type of plant or animal (species) there is in a given ecosystem