AGRN test 4

  1. types of reproduction
    • sexual
    • asexual
  2. reproduction by vegitative structures
    asexual reproduction
  3. advantage of asexual repro
    uniform progeny
  4. disadvantage of asexual repro
    less genetic variability to select improved varieites
  5. repro resulting from the fertilization of ovules and subsequent formation of viable seed
    sexual reproduction
  6. the union of pollen nucleus with the egg nuclei
  7. transfer of pollen from the stamen to the pistil
  8. plants where the pistil is pollinated by the stamen of the same plant
    self-pollinated plants
  9. plants whose pistil is pollinated with pollen from different plants by insects or wind
    cross-pollinated plants
  10. unique characteristics controlled by one or more genes
  11. unit of inheritance passed from parents to offspring located on chromosomes
  12. forms of a gene
  13. allele expressed only in homozygous condition
    recessive allele
  14. allele that expresses itself whenever present
    dominant allele
  15. when reproductive cells are formed, the gene pairs seperate and are distributed as units to each gamete
    law of segregation
  16. the distribution of one pair of factors is independent of the distribution of other pairs
    law of independent assortment
  17. alleles must be on different chromosomes
    law of independent assortment
  18. hybridization involving a single allele
    monohybrid cross
  19. hybridization involving two alleles
    dihybrid cross
  20. what is the purpose of plant breeding?
    to produce new crop cultivars and varieties with improved agronomic traits
  21. what is considered during plant breeding?
    • yield
    • pest resistance
    • maturity
    • quality
    • response to speceific situations
  22. the extent to which a plant's phenotype is the result of the genotype rather than the environment
  23. equation of heritability
    phenotype= genotype+environment
  24. how to figure out heritability
  25. the greater the heritability,
    the greater the chance to develop plants with that trait
  26. factors affecting crop production that is the result of growing conditions
    environmental variations
  27. examples of differences in environmental variations
    • soil type
    • fertility
    • pest infestation
  28. how do you test for environmntal influence?
    grow plants with similar heredity in different environments
  29. variation that results from genetic differences
    heredity variation
  30. genetic variability originates from
    • gene recombinations after hybridization
    • mutations
    • polyploidy
  31. sudden changes in heredity material of a cell
  32. what do mutations result from?
    • change in gene from one allele to another
    • rearrangement of chromosome material
    • loss or duplication of chromosome segments
  33. typically, mutations are
  34. are mutations dominant or recessive?
    typically recessive
  35. a condition in which individuals have more than 2 chromosome sets or genomes in their somatic cells
  36. what is the significance of polyploidy
    • adds genetic diversity
    • recessive traits are more likely to appear
  37. what is the purpose of selection?
    to select a plant with superior features
  38. the selection of a quantity of plants with similar characteristics while still maintaining some diversity in the gene pool
    mass selection
  39. the improvement of a trait of a hybrid over its parents
  40. a form of recurrent hybridization by which a superior characteristic may be added to an otherwise desirable variety
  41. how is backcrossing done?
    two parents are crossed where one is a productive variety which lacks some superior quality and another with a superior quality but is otherwise not desierable
  42. a species is a group of organisms that
    • mate
    • produce viable offspring
    • offspring also mate and produce viable offspring
  43. subspecies
    members of hte same species that have become geographically isolated
  44. an organism with one or more genes from another species
  45. naturalists began to identify hybrids of plants (began plant breeding)
  46. Gregor mendel- father of modern genetics
  47. Louis Pasteur defines role of micro-organisms and establishes the science of microbiology
  48. first in vitro culture of a whole plant
  49. Watson & Crick discovered the double helix of DNA
  50. green revolution-introduction of hybrid crops into food-short third world
  51. researches able to isolate genes
  52. discovery of plasmids and restriction enzymes in bacteria
  53. recombinant DNA technology discovered
  54. the ability to transfer pieces of genetic info from one organism to another
    gene splicing or genetic engineering
  55. first commercial application of gene splicing; human insulin for diabetes
  56. first genetically engineered plant
    • 1983
    • tobacco
  57. plants ressitant to insects, viruses and bacteria; first field tests
  58. field trial for Bt cotton
  59. Monsanto created; approved for sale
  60. round up ready cotton first commercialzied
  61. YieldGard corn sold in US
  62. GMO crops used
    • soybeans
    • cotton
    • corn
    • canola
  63. organisms taht have one or more genes fro ma different species using recombinant DNA technology
    transgenic plants (GMO)
  64. what is the goal of transgenic plants?
    design organisms with specific characteristics by the artificial insertion of genes from other species
  65. discrete segments of DNA that encodes the info necessary for assembly of a specific protein-trait
  66. production of multiple copies of a gene
    gene cloning
  67. recombination or joining DNA segments from two different species
    Recombinant DNA
  68. enzyme that cuts stands of DNA at specific places
    restriction enzyme
  69. enzyme that can join sticky ends of two strands of DNA
    DNA ligase
  70. delivery vehicle used to introduce rDNA into a host cell
  71. molecules of DNA that are found in bacteria seperate from the bacterial chromosome
  72. changes in the DNA sequence of a gene
  73. steps of genetic engineering
    • isolate desired gene
    • remove DNA from donor with restriction enzyme
    • transfer novel gene to the host through a vctor
  74. a soil bacterium that causes crown galls in many plants
    Agrobacterium tumefaciens
  75. how does agrobacterium tumefaciens work?
    • in vivo infection requires wounding of the plant tissue
    • the bacteria attaches to the cell wall and is activated by compounds from the wounded cell
  76. how does the gene cannon work?
    minute metal beads of gold coated with DNA are shot directly into plant cells and as the plant heals, some of the DNA is incorporated into the plant
  77. what plants are resistant to broad spectrum herbicides (round up ready)
    • corn
    • cotton
    • soybeans
    • canola
  78. what bacteria is the gene donor in round up ready GMOs?
  79. how do round up ready GMOs work?
    degrades herbidice inside the plant
  80. what plants are Bt crops?
    • cotton
    • potatoes
    • corn
  81. what is the gene donor in Bt crops?
    bacillus thuringiensis
  82. how do Bt crops work?
    insecticidal toxin for control of catepillars
  83. what are the pro's of transgenic crops?
    • cost effective
    • fewer pesticides needed
  84. what are the con's of transgenic crops?
    • more pesticides needed
    • cost
    • more evolutionary pressure; greater chance of resistance
    • possibility of transferring genetic materials to other organisms
    • environmental consequences
    • effects on non-target organisms (allergins, toxins)
Card Set
AGRN test 4
test 4