Animals

• What is a species?

  A group of organisms that can reproduce
• What do members of the same species have in common?

  Very similar characteristics
• What is an example of variation in tigers?

  Variation in the stripes of tigers
• What causes environmental variation?

  Environmental factors in an organism's surroundings
• What are the two types of environmental factors?

  Living and physical environmental factors
• What is environmental variation?

  Variation caused by environmental factors
• What forms an ecosystem?

  All organisms and physical environmental factors
• How do offspring inherit characteristics?

  From their parents
• What is inherited variation?

  Variation in characteristics inherited from parents
• What controls an organism's characteristics?

  Genetic information in DNA
• Who discovered the structure of DNA?

  James Watson and Francis Crick
• What do chromosomes contain?

  A long molecule of DNA
• How many types of chromosomes are in humans?

  23 different types
• What forms a zygote?

  Fusion of two gametes during fertilisation
• How can scientists express probabilities of inheritance?

  As percentages, decimals, or fractions
• What is adaptation in organisms?

  Characteristics that allow survival in a habitat
• What do gametes contain in terms of chromosomes?

  One copy of each type of chromosome
• Give an example of an adapted animal.

  Jack rabbits in a desert habitat
• What does a bell curve represent in variation?

  Normal distribution of a characteristic
• What does natural selection explain?

  How some members survive better than others
• How might a new predator affect jack rabbits?

  Some may survive better due to longer legs

  
• What is the process of natural selection?

  Survival and reproduction of the fittest
• Who proposed the idea of natural selection?

  Charles Darwin and Alfred Russel Wallace
• What can cause species to become endangered?

  Changes in ecosystems and human activities
• What are the main causes of endangerment and extinction?

  • Changes in physical environmental factors
  • Competition from other organisms
  • Disease
  • Human activities (e.g. hunting, habitat clearing)
• How can we preserve biodiversity?

  • Protecting areas and setting up nature reserves
  • Establishing breeding programs in zoos
  • Banning hunting of certain animals
  • Setting up gene banks for organisms
• Why should we preserve biodiversity?

  • Organisms depend on one another (interdependence)
  • Utilization of organisms if they become extinct
  • Biodiverse areas recover better from disasters