Lecture 8 Flashcards
Define genetic modification
vitro alteration (lab) of genetic material (DNA or RNA) and the re-introduction of the altered genetic material into a living organism
Define genetic engineering
the manipulation of genetic material for practical purposes. Also called recombinant DNA technology.
Define genetically modified organism (GMO)
An organism whose genome contains DNA from the same or different species, that has been modified by methods of genetic engineering.
Define transgenic plant
genetically modified crops
Define transgene
an exogenous gene introduced into the genome of another organism either by artificial techniques
Define T-DNA
transferred DNA
true or false; plant tissues can grow in culture indefinitely; can grow shoots and roots in culture
true
true or false; single cells of plants can grow into whole plants (regenerated)
true
Define totipotent
cells that produce all the cell types of a plant
true or false; totipotency allows cloning of genetically identical individuals
true
Describe the cloning process of a plant using a carrot as an example
- ) fragments were cultured in nutrient medium
- ) stirring
- ) caused single cells to shear off into the liquid
- ) single cells free in suspension begin to divide
- ) embyronic plant developed from a cultured single cell
- ) plantlet cultured in an agar medium
- ) planted into soil
- ) adult plant
Define adventitious shoots , roots, meristems
arising from an unusual place
Define callus cells
undifferentiated, fast growing cells
- many types from soft, white, friable, to hard, green, lumpy
Define explant
piece of tissue excised from the plant and cultured in vitro
how do new tissue an plants arise from culture
from dedifferentiation, induced morphogenesis and differentiation
What are the types of tissue culture
- ) protoplast fusion (cells without walls)
- ) meristem culture
- ) organogenesis
- ) embryogenesis
what is protoplast fusion
- protoplasts isolated from leaf tissue
- remove cell wall
- fused via electroporation or PEG chemicals
true or false; fusion can result in incompatibilities and loss of chromosomes
true
What does meristem culture mean
(shoot tip culture, bud culture)
- culture of pre-existing meristems —> growth and division
What does organogenesis mean
de novo (new formation) of organs from single cells (small clumps of cells); shoots first then regenerate roots
What does embryogenesis mean
de novo formation (new formation) of embryos from single cells or small clumps of cells (roots and shoots at the same time); no use of seeds
How is organogenesis carried out in African violets
using leaf pieces
What is Agrobacterium
full name: Agrobacterium tumifaciens
- causes crown gall disease
- an outgrowth of fast growing, non-differentiated cells
- types of soil bacteria
- infects at wound sites of plant
How does Agrobacterium act as a natural genetic engineer
transfers part of its DNA, the T-DNA into plant cells
- introduced any cloned gene into the modified T-DNA and let agrobacterium introduce it into the plants for you
When was agrobacterium first modified to become a genetic engineer
1970s - 1980s
What is the general process of modifying the agrobacterium plasmid
- ) restriction enzymes cut
- ) incorporation of cloned gene via sticky ends (replace the T-DNA gene)
- ) recombinant plasmid results
- ) plasmid is introduced to agrobacterium nucleus
- ) agrobacterium infects desired plant with the desired gene
What is the process of making genetically engineered plants
- ) agrobacterium with recombinant DNA infects plant
- ) select transgenic callus; callus came from cells along the cut surface into which Agrobacterium has put its DNA containing the foreign gene
- ) give hormones (eg. auxin: cytokinin) the callus induced to produce shoots and roots to give a plant form what was originally a single cell
How to make a transgene contruct
YFG (arrow)
left; promoter sequence
—–> overall trangene
transgene is put into binary vector
what is LUC
luciferase gene (reporter gene; acts as a marker) - attaches to a plant promoter that is expressed most highly in vascular bundles
true or false; transgenes are a powerful scientific tool for understanding gene function and basic biological processes
true
What are examples of how transgenes are used as a scientific tool for understanding gene function
- ) ethylene as a ripening hormone (petunias)
- ) ethylene as a senescence hormone (petunia)
- ) Cytokinin as an anti senescence hormone
- ) Apple Myb10 regulating anthocyanin production (eg. apples)
