Summary: Biology Final

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• Bio Final

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• -The change in allele frequencies in a population from generation to generation-The many organisms that inhibit our planet are fit with their environment as a result of this...-Leads to diversity among organisms-Can explain how it is that many characteristics are shared by very different organisms (unity)     -Can also explain the diversity of organisms on earth

  Evolution 
  *The evolution of populations can occur at different rates
     -A population is the smallest scale at which evolution can occur
          -Evolution occurs at the level of the population, not at the level of the individual
  
  *To organize the info. about diverse life forms, a HIERARCHICAL SYSTEM was developed and BINOMIAL NOMENCLATURE uses to identify species

• -A Theory of evolution-A nonrandom evolutionary process that adapts a population to its environment, so it results in diverse evolutionary adaptations -The environment determines the reproductive success of the individual phenotype 

  Natural Selection
  
  *Groups of organisms evolve when natural selection favors individuals with advantageous inherited characteristics 
  *When natural selection acts differently on 2 populations, they may emerge as 2 new species descended from one ancestral population
  *Any inherited characteristic that enables an individual to function better than others in that habitat makes that individual more likely to survive and reproduce and to pass those characteristics on (FITNESS) 

• Focuses on evolutionary changes in frequency of genes that occur over relatively short periods of time-Change in allele frequencies in a population over successive generations

  Microevolution

• Studies the history of life from the perspective of the formation and extinction of species and other large-scale consequences of population-level changes

  Macroevolution

• 1) Fossils2) Traces of evolutionary history in existing organisms3) Similarities and divergences in DNA4) Direct observations of genetic change in populations5) Continental drift6) The present-day formation of new species

  Evidence for Biological Evolution
  *very strong evidence

• The preserved remains, or their impressions, of formerly living organisms, which enable biologists to reconstruct the history of life on earth-Records show many intermediate species that exhibit some similarities to the ancestral group and some similarities to the descendant species *Intermediate species ARE MISSING LINKS

  Fossils

• Patterns of growth are inherited (carried in the genes) -The pattern in the very earliest stages of life can provide evidence of an organism's evolutionary past-The manner in which an embryo develops, especially at the early stages, may mirror early developmental stages of ancestral forms

  Organisms contain evidence of their evolutionary history

• Reduced or degenerate parts whose function is no longer needed

  Vestigial organs

• Similar features of organisms related to one another through common descent are said to be....

  Homologous
  
  *Similarities among organisms can explain the fact that organisms that share similar characteristics evolved from a common ancestor

• Occurs when natural selection causes distantly related organisms to evolve similar structures in response to similar environmental challenges

  Convergent evolution 
  
  *Characteristics that result from convergent evolution are said to be ANALOGOUS