Biology 1115 Chapter 22

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  1. Darwin noted that current species are ______________.
    descendants of ancestral species
  2. Define evolution.
    Descent with modification
  3. How did Aristotle view species?
    he viewed species as fixed
  4. How did Carolus Linnaeus interpret organismal adaptations?
    he interpreted them as evidence that the Creator has designed each species for a specific purpose
  5. What did jean-baptiste Lamarck hypothesize about species evolving?
    that species evolve through the use and disuse of body parts and the inheritance of acquired characteristics
  6. What did Lyell's principle of uniformitarianism state?
    • states that the mechanisms of change are constant over time
    • this greatly influenced Darwin's thinking
  7. What was Darwin influenced by?
    Lyell's Principle's of Geology
  8. In reassessing his observations, Darwin perceived ______________ and ____________ as closely related processes.
    • adaptation to the environment
    • origin of new species
  9. What are the 2 main ideas Darwin developed?
    • Descent with modification: explains life's unity and diversity (pattern)
    • Natural Selection: cause of adaptive evolution (process)
  10. What does the phrase "descent with modification" mean?
    refers to the view that all organisms are related through descent from an ancestor that lived in the remote past
  11. What is artificial selection?
    modifying species by selecting and breeding individuals with desired traits
  12. Darwin described four observations of nature and from the drew 2 inferences. What are the  observations?
    • 1. members of a population often vary greatly in their traits
    • 2. traits are inherited from parents to offspring
    • 3. all species are capable of producing more offspring than the environment can support
    • 4. b/c of lack of food & other resources, many offspring don't survive
  13. Darwin described four observations of nature and from the drew 2 inferences. What are the 2 inferences?
    • 1. Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals
    • 2.This unequal ability of  individuals to survive and reproduce will lead to the accumulation of favourable traits in the population over generations
  14. What process explains the match between organisms and the environment?
    If some heritable traits are advantageous, these will accumulate in the population, and this will increase the frequency of individuals with adaptations.
  15. What does natural selection increase?
    Natural selection increases the adaptation of organisms to their environment over time
  16. If an environment changes over time, how will natural selection effect it?
    natural selection may result in adaptation to these new conditions and may give rise to new species
  17. __________ do not evolve, __________ evolve over time.
    • individuals
    • populations
  18. Natural selection does not create new traits, but edits or selects for traits ____________ in the population.
    already present
  19. Adaptations vary with __________________.
    different environments
  20. What is an example of evidence for ongoing natural selection?
    evolution of antibiotic resistant bacteria
  21. A drug does not _______ drug resistant pathogens
  22. The use of antibiotics to kill bacteria _________ for bacteria resistant to these drugs.
  23. Define homology.
    is similarity resulting from common ancestry
  24. Define homologous structures.
    • common ancestors
    • same basic structures
    • sometime different use
  25. What are vestigial structures?
    • are remnants of features that served important functions in the organism's ancestors.
    • structures we don't use anymore
  26. what is an example of homologies at the molecular level?
    genes shared among organisms inherited from a common ancestor.
  27. What are evolutionary trees?
    are hypotheses about the relationships among different groups
  28. convergent evolution produces?
    analogous structures
  29. define convergent evolution.
    evolution of analogous structures in distantly related groups
  30. What are analogous structures?
    • different ancestors
    • different basic structures
    • same function
Card Set
Biology 1115 Chapter 22
Descent with modification
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