Variation and 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 describes 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 do genes code for?

  Proteins
• What is a genome?

  All of your genes combined
• Why does everyone except identical twins have a unique genome?

  Different combinations of proteins
• How can the environment affect identical twins' height?

  Through differences in diet and sleep
• What is the key point about characteristics determined by genes and environment?

  Most characteristics are influenced by both
• What causes genetic variation?

  Mutations
• What is a mutation?

  A change in the DNA code
• What happens to most mutations?

  They don't affect the phenotype
• What can beneficial mutations do?

  Make individuals more resistant to diseases
• What did Charles Darwin notice about certain traits?

  They were passed on from parent to child
• What term did Darwin use to describe the survival of the fittest?

  Natural selection
• What does the concept of evolution describe?

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

  They evolved from simple life forms
• What evidence supports Darwin's theory of evolution?

  Development of antibiotic resistance in bacteria
• What happens to phenotypes of two different populations over time?

  They may become so different they can't interbreed
• What are the key points of natural selection and evolution?

  • Natural selection leads to evolution
  • Genetic changes give rise to advantageous phenotypes
  • Over time, populations may diverge into new species
• How does natural selection contribute to the evolution of species?

  • Fittest individuals survive and reproduce
  • Beneficial traits are passed to offspring
  • Over generations, this leads to species changes
• What are the implications of Darwin's theory of evolution?

  • All species evolved from earlier forms
  • Evolution is a gradual process over time
  • Evidence includes fossil records and observed changes