bio 112 ecology and evolution test one eku

  1. 7 Characteristics of Life?
    • 1. Cells and Organization
    • 2.Energy use and Metabolism
    • 3. Response to Environmental Changes
    • 4. Regulation and Homeostasis
    • 5. Growth and Development
    • 6. Reproduction
    • 7. Biological Evolution
  2. Scientific Method?
    • Observation
    • Hypothesis
    • Test the Hypothesis (experiment)
    • Analyze results
    • reject or fail to reject hypothesis.
    • (Never Prove Hypothesis)
  3. Alleles?
    Different versions of the same gene.
  4. Genotype?
    the types of genes (alleles) present
  5. Homozygous?
    two of the same alleles (RR or rr)
  6. Heterozygous?
    two different alleles (Rr)
  7. Phenotype?
    physical appearance, determined by the genotype.
  8. Dominant Traits?
    traits that are expressed, represented by a capital letter.
  9. Recessive Traits?
    only seen when homozygous, represented by a lowercase letter.
  10. Mendelian Genetics
    Punnett Squares and probability.
  11. Monohybrid cross?
    Hommozygous Dominant crossed with a homozygous recessive.
  12. Law of Dominance
    In the monohybrid cross (mating of two purebred organisms that differ in only one character), one version disappeared. There is a change in genotype, all are heterozygous.
  13. Dihybrid crosses?
    • Crosses involving two genes simultaneously.
    • Ex: Mendel's peas: seed color and seed shape are on different chromosomes.
  14. Population?
    • A group of individuals of the same species, occupying the same space/environment, that can interbreed.
    • Ex: Squirrels in Central Park
  15. H-W Equilibrium
    an equation, describes relationships between alleles and genotype frequencies (in a population that is not evolving)
  16. Evolution
    Changes in populations of organisms over time.
  17. H-W Assumptions
    • No mutations
    • No natural selection
    • Infinitely large population
    • No migration between populations
    • Random mating
  18. Forces of Evolution?
    • Mutation
    • Genetic Drift
    • Natural Selection
    • Migration
    • Nonrandom mating
  19. Fitness
    • Relative likelihood that a genotype will contribute to the gene pool of the next generation as compared with other genotypes
    • Measure of Reproductive Success
    • The ability to survive and reproduce
  20. Types of Selection?
    • Phenotypes can be selected by humans to reproduce (artificial selection)
    • Adaptation that increases survival and reproduction in a particular environment (natural selection)
  21. Natural Selection
    Individuals that survive and reproduce (have greater Fitness) will lead to a change in allele frequencies over time
  22. Artificial Selection
    • Does not depend on the ability to survive or reproduce based on environmental conditions.
    • Human induced
  23. 4 Observations of Natural Selection
    • Individuals within populations vary
    • Some of the variation among individuals can be passed to offspring
    • Populations of organisms produce more offspring than will survive
    • Survival and reproduction are not random
  24. Patterns of Natural Selection
    • Directional
    • Stabilizing
    • Diversifying
    • Balancing
  25. Directional Selection
    Individuals at one extreme of a phenotypic range have greater survival/reproductive success
  26. Stabilizing Selection
    Individuals with intermediate phenotypes have greater survival/reproductive success
  27. Diversifying Selection
    Two or more different genotypes/phenotypes are favored; often occurs in heterogeneous environments
  28. Balancing Selection
    • increases genetic diversity
    • creates a balanced polymorphism (2+ alleles are kept in balance and maintained in the population)
    • Has heterozygote advantage, and negative frequency-dependent selection
  29. Sexual Selection
    • form of natural selection
    • directly promotes reproductive success
  30. Intrasexual selection
    • between members of the same sex
    • males directly compete for mating opportunities or territories
  31. Intersexual Selection
    • between members of the opposite sex
    • female choice
  32. Genetic Drift
    • changes in allele frequencies due to random change
    • Allele frequencies may "drift" randomly from one generation to the next
    • happens regaurdless of fitness
    • faster in smaller populations
  33. Bottleneck
    • populations reduced dramatically and then rebuilds
    • randomly eliminated members without regard to genotype
    • surviving members may have allele frequencies different from original population
    • new population likely to have less genetic variation
  34. Founder effect
    • small group separates from larger population and establishes new colony
    • relatively small founding population expected to have less genetic variation
  35. Migration
    gene flow occurs when individuals migrate between populations having different allele frequencies
  36. Nonrandom Mating
    • assortative mating
    • disassortative mating
  37. Assortative Mating
    • Individuals with similar phenotypes are more likely to mate
    • increases the proportion of homozygotes
  38. Disassortative Mating
    Dissimilar phenotypes mate preferntially, favors heterozygosity
  39. Inbreeding
    • choice of mate based on genetic history
    • does not favor any particular allele but it does increase the likelihood the individual will be homozygous
    • negative consequences with regard to recessive alleles
    • lower mean fitness
    • inbreeding depression
  40. Neutral Theory of Evolution
    • much of the modern variation in gene sequences is explained by neutral variation rather than adaptive variation
    • sequencing data supports this data
Card Set
bio 112 ecology and evolution test one eku
eku bio 112 test one