yr11 biology mixed deck

• Classification


  • Descriptive Groups
  • Vertebrates
  • Invertebrates
  • Flowering Plants
  • Non-flowering plants
• Classification


  Putting things into groups to understand the variety of living things, how they have changed over time, and how they are related through evolution
• Binomial system


  Organisms are given two names - the genus and the species
• The scientific/Latin name has advantages over common names
• Scientific classification of domestic dog, coyote, and fox

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Mammalia
  • Order: Carnivora
  • Family: Canidae
  • Genus: Canis (dog, coyote)
  • Genus: Vulpes (fox)
  • Species: lupus (dog), latrans (coyote), vulpes (fox)
• Adaptations


  • Morphological (shape) and behavioural adaptations that enable organisms to survive in their environment
• Adaptations of arctic fox and fennec fox

  • Morphological: Ear length, coat colour, body mass
  • Behavioural: Fennec fox is nocturnal to avoid desert heat
• Population size


  How many of one type of plant or animal (species) there is in a given ecosystem
• Factors affecting population size

  • Competition for food and water
  • Number of predators
  • Disease
  • Pollution
• Organisms better adapted to the environment are more successful and reproduce more
• Interspecific competition


  Competition between members of different species
• Intraspecific competition


  Competition between members of the same species
• Biodiversity


  The number of different species in an ecosystem
• Animal population size


  • Affected by:
  • Competition for food and water
  • Number of predators
  • Disease
  • Pollution
• Plant population size


  • Affected by:
  • Competition for light, water or minerals
  • Number of herbivores
  • Disease
  • Pollution
• Animals will compete for food and water
• Plants will compete for light, water and minerals
• Organisms better adapted to the environment


  More successful, reproduce more, have more offspring
• Biodiversity


  The number of different species in a particular area and the numbers of individuals within those species
• Importance of biodiversity


  • Food
  • Potential foods
  • Industrial materials
  • New medicines
  • Human well being
• More and more species are becoming extinct because man is destroying their habitats, leading to a decrease in biodiversity
• Reasons for habitat destruction

  • Building
  • Industry
  • Agriculture
• Methods of protecting biodiversity and rare species

  • CITES (Convention on International Trade in Endangered Species)
  • SSSI - Sites of Special Scientific Interest
  • Captive breeding programs (e.g. Zoos)
  • National Parks
  • Seed banks
  • Local biodiversity conservation schemes
• Quadrat


  A square used to study plant cover and count the number of each species of plant inside it
• Using quadrats to study plant cover

  1. Select a random sampling method

  2. Place a 1m2 quadrat randomly

  3. Count the number of living organisms or percentage cover in the quadrat

  4. Repeat at least twice or until numbers are consistent

  5. Calculate the average

  6. Multiply to calculate the total in the whole area
• Monitoring changes in organism numbers over time

  1. Use quadrat method to calculate number at start

  2. Use quadrat method to study same area after a set period

  3. Note the change to identify a pattern
• Transect


  A series of quadrat samples taken in a line, used to find the distribution of species in a habitat
• Transects can show the frequency and distribution of species in a habitat
• Conditions for accurate population estimates

  • Sample area must be typical of whole area
  • Bigger sample area is better
  • Sampling method must not affect results
• Samples cannot be absolutely accurate, so scientists use statistical analysis that takes account of sample size
• Capture-recapture technique for measuring animal populations

  1. Capture a number of individuals, mark them, release them back

  2. Capture another sample some time later

  3. Use a mathematical equation to estimate the population
• Conditions for accurate capture-recapture estimates

  • Enough time has passed between samples for marked individuals to mix
  • No large-scale movement of the population in or out of the area
• N


  Estimate of total population size
• M


  Number of animals captured and marked on first visit
• C


  Number of animals captured on second visit
• R


  Number of animals captured on second visit that were marked
• Example


  • 50 water beetles were caught and marked (M), before being returned to their pond. The next day, 35 water beetles were caught (C), 10 of which had been marked (R).
• Capture-recapture technique


  1. M = 50

  2. C = 35

  3. R = 10

  4. N = (M*C)/R = 175
• Conditions for accurate population estimate


  • Enough time has passed between the two samples for the marked individuals to mix with the rest of the population
  • No large-scale movement of animals in or out of the area in the time between the two samples
  • The marking technique does not affect the survival chances of the animal
  • The marking technique doesn't affect the chances of being recaptured
• Assumptions of the capture-recapture technique