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 with the same genes?

  Different diets or sun exposure can alter traits
• What is the key point about our characteristics?

  Most are determined by genes and environment
• What causes genetic variation?

  Mutations
• What is a mutation?

  A change in the DNA code
• Do most mutations affect the organism's phenotype?

  No, most mutations have no effect
• What happens when mutations do change proteins?

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

  Increased resistance 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?

  Survival of the fittest
• What concept did Darwin's theory 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 signifies the formation of a new species?

  Inability to produce fertile offspring
• What is the summary of evolution through natural selection?

  • Evolution occurs through natural selection
  • Genetic changes lead to advantageous phenotypes
  • Over time, populations may diverge significantly
  • New species can form when interbreeding is no longer possible