Variation & evolution

• What can lead to huge variation between individuals?

  Differences in genes and environment
• What is the process called that can lead to the evolution of new species?

  Natural selection
• What term is used to describe the differences among individuals in a population?

  Variation
• What does a phenotype describe?

  Observable characteristics of an individual
• What two factors interact to determine a phenotype?

  Genes and environment
• What is a genome?

  All of your genes combined
• How can the environment affect identical twins with the same genes?

  Different diets or sun exposure can alter traits
• What influences most of our traits?

  Many different genes and environmental factors
• What causes genetic variation?

  Mutations in the DNA code
• What is a mutation?

  A change in the DNA code
• How do most mutations affect proteins?

  They usually have no effect
• What happens when mutations do change proteins?

  The phenotype may change slightly
• What is a potential outcome of beneficial mutations?

  Increased resistance or improved abilities
• What concept did Darwin's theory of evolution describe?

  Inheritance of characteristics over generations
• What does the theory of evolution imply about current species?

  They evolved from different species in the past
• What evidence supports Darwin's theory of evolution?

  Development of antibiotic resistance in bacteria
• What does evolution occur through?

  Natural selection of genetic changes
• What can happen to phenotypes of two populations over time?

  They may become so different they can't interbreed
• What is formed when two populations can no longer interbreed?

  A new species
• What are the main points of Darwin's theory of natural selection?

  • Traits are passed from parent to child
  • Fittest individuals are more likely to survive
  • Beneficial mutations increase survival chances
  • Evolution occurs over multiple generations
• What evidence supports the theory of evolution?

  • Development of antibiotic resistance in bacteria
  • Fossil records showing gradual changes
  • Genetic studies revealing relationships among species
• How do genes and environment interact to influence traits?

  • Genes provide the potential for traits
  • Environment can enhance or inhibit trait expression
  • Both factors together determine the observable phenotype