Biology Test 2

  1. Autosomal dominant
    • Phenotype gene comes from sex chromosome
    • Trait typically appears in every generation
  2. Autosomal recessive
    • Phenotype gene does not come from sex chromosome
    • If both parents are heterozygous, child will have a 25% chance of being affected
  3. Law of Segregation
    • Alleles segregate into different haploid cells that eventually give rise to gametes
    • During fertilization, male and female gametes randomly combine with each other
  4. X-linked Recessive Inheritance
    • Males show disorder more than females
    • Son cannot inherit disorder from his father
  5. Law of Independent Assortment
    Genes on different chromosomes segregate independent of one another
  6. Phases of Mitosis
    • Prophase: chromosomes composed of two chromatids
    • Metaphase: chromosomes align at spindle equator
    • Anaphase: sister chromatids of chromosomes separate
    • Telophase: two nuclei (2n)
  7. Product rule
    • Probability that two or more independent events will occur is equal to the product of their individual probabilities
    • 1/2 x 1/2 = 1/4
  8. How can you tell how many genetically different gametes you can make?
    • It depends on how many loci are heterozygous and on different chromosomes
    • 2 alleles can be made for each heterozygous locus
    • AAFfEdYyDDIIKKJj = 16
  9. Sum rule
    • Probability that one of two or more mutually exclusive outcomes will occur is the sum of the probabilities
    • 1/4 + 1/4 = 1/2
  10. Balancing selection
    Occurs when natural selection maintains stable frequencies of two or more phenotypic forms in a population
  11. 5 Conditions of Genetic Equilibrium
    • No mutation
    • Random mating
    • Gene doesn't affect survival or reproduction
    • Large population
    • No immigration/emigration
  12. Allele frequency equation
    Allele frequency = (number of copies of a specific allele in population)/(Total number of all alleles for that gene in a population)
  13. Genotype frequency equation
    Genotype frequency = (number of individuals with a particular genotype in population)/(Total number of individuals in a population)
  14. Absolute fitness
    Actual number of surviving offspring with a particular genotype produced between generations
  15. Relative fitness
    Number of surviving offspring of one genotype compared to a different genotype
  16. Directional Selection
    Individuals of one extreme phenotype favored
  17. Stabilizing selection
    • Individuals with intermediate phenotype favored
    • Extreme phenotype selected against
  18. Disruptive Selection
    • Both extreme phenotypes favored
    • Intermediate phenotypes selected against
  19. Effects of genetic drift
    • Genetic drift is significant in small populations
    • Causes allele frequencies to change at random
    • Can lead to a loss of genetic variation within populations
    • Can cause harmful alleles to become fixed
  20. Neutral variation
    Genetic variation that appears to confer no selective advantage or disadvantage
  21. Epistasis
    Multiple alleles at multiple loci interacting and affecting a trait
  22. Pleitropy
    Alleles at a single locus may affect 2 or more traits
  23. Continuous variation
    A continuous range of small differences in a given trait among individuals
  24. Extranuclear Inheritance
    Some genes are not found on the chromosomes in the cell nucleus. Like in mitochondria and chloroplasts
  25. Mitochondria are inherited by which parent?
  26. Y chromosome is inherited from which parent?
  27. What is the Two Fold Cost of Sex?
    Asexual reproduction passes on 100% of genetic info but sexual reproduction only passes on 50% from the mother
  28. Intrasexual selection
    When members of one sex compete for territory and resources in order to get a mate
  29. Intersexual selection
    • Female choice
    • Females choose male mates based on a criterion that reflects ability to provide resources and/or quality of genes
  30. Sexual dimorphism
    Change of appearance, such as molting into new feathers, during breeding season to attract new mates
  31. Selection pressure
    Influence a particular factor has on the ability of an organism to survive and reproduce
  32. Cladogenesis
    • Lineage splits, isolated populations diverge
    • Branching pattern
  33. Anagenesis
    • Changes occur within a single lineage (no branching)
    • Gene flow throughout process
  34. Monophyletic
    Taxon contains a common ancestor and all of its descendants
  35. Paraphyletic
    Taxon contains its most recent common ancestor, but does not contain all the descendants of that ancestor
  36. Polyphyletic
    Common ancestor(s) not in group
  37. Apomorphy
    Derived or specialized character or character state
  38. Plesiomorphy
    An ancestral or primitive character or character state
  39. Macroevolution
    • Long-term result of microevolutionary processes
    • Patterns and trends among major lineages
  40. Speciation
    When a species branches off from its native habitat and variation occurs
  41. Microevolution
    • Natural selection
    • Genetic drift
    • Mutation
    • Gene flow
  42. Prezygotic barrier and types
    • Something preventing fertilization between 2 groups of the same species
    • Habitat isolation
    • Temporal "    "
    • Behavioral "   "
    • Mechanical "   "
    • Gametic  "  "
  43. Biological Species Concept
    Species are kinds of organisms that are reproductively isolated from one another
  44. Ecological Species Concept
    Species occupy different ecological niches
  45. Recognition Species Concept
    Members of the same species recognize one another as potential mates
  46. Phylogenetic Species Concept
    Species is a basal cluster of organisms that is distinct from other such clusters and shows a pattern of ancestry and descent
  47. Gradualism
    • Each new species evolves continuously over long spans of time
    • Large phenotypic differences that produce new species are due to the accumulation of many small genetic changes
  48. Punctuated Equilibrium
    • Tempo of evolution more sporadic
    • Species in equilibrium for long periods and then short rapid bursts of changes
  49. Allopatric speciation
    No contact between populations
  50. Parapatric speciation
    Populations share a border area
  51. Sympatric speciation
    Continuous contact between populations
  52. Habitat Isolation
    2 different habitats
  53. Behavioral Isolation
    Species specific behaviors
  54. Mechanical Isolation
    Physically cannot mate
  55. Gametic Isolation
    Gametes are shared purely randomely
  56. Postzygotic Barriers and types
    • Two species can breed but something prevents their offspring from thriving
    • Allopatric Speciation
    • Sympatric Speciation
  57. Morphological Species Concept
    A species is a set of individuals with morphological features in common.
  58. Androecium
    • Anther and filament
    • Male gametes in plants
  59. Gynoecium
    • Pistil, stigma, ovary/carpels
    • Female gametes in plants
  60. Biotic pollination
    Animals move pollen from one flower to another
  61. Types of pollinator attractants
    • Primary: food, shelter, other needed materials
    • Secondary: odor, visual cues
  62. Pseudocopulation
    Plants that mimic females of pollinator species to trick it into mating the flower and collect pollen
  63. What is the root system's function?
    • Anchors the plant
    • Used to absorb water and ions
  64. What is the function of the shoot system?
    • Consists of supporting stems, photosynthetic leaves, and reproductive flowers
    • Repetitive units consist of internode, node, leaf, and axillary bud
  65. Node
    Point of attachment of leaf to stem
  66. Internode
    Area of stem between two nodes
  67. Blade
    Flattened part of leaf
  68. Petiole
    Stalk of leaf
  69. Axil
    Angle between petiole/blade and stem
  70. Axillary bud
    Develops into branches with leaves or may form flowers
  71. Terminal bud
    Extends the shoot system during the growing season
  72. 3 Basic Tissue Types in Plants and functions
    • Dermal: outer protective cover
    • Ground: function in storage, photosynthesis, and secretion
    • Vascular: conducts fluids and dissolved substances
  73. 3 Ground Tissue Cell Types and functions
    • Parenchyma: function in storage, photosynthesis, and secretion
    • Collenchyma: provide support and protection, kinda soft
    • Sclerenchyma: dead, hard cells that provide protection and support
  74. Two types of sclerenchyma cells
    • Fibers: long, slender cells that are usually grouped in strands
    • Sclereids: variable shape, often branched, may occur singly or in groups
  75. Two types of Vascular Tissue and function
    • Xylem: principle water-conducting tissue.
    • Phloem: nutrient transportation
Card Set
Biology Test 2
test 2