Final Exam Flashcards
Plant Biotech
Utilization of plant products and processes
-Tissue Culture-growing whole plants from cells
-gene/genome sequencing
-biofuel production
Importance of Genome Projects
-Helps us understand the ancestry of species.
-Provides information about what genes are responsible for conferring specific traits.
- Used agronomically
Transgenic Plants
Plants in which DNA from another species (with which the plant could not cross) has been integrated.
-These plants are generated through transformation: the genetic manipulation of a cell resulting from delivery and incorporation of DNA into the recipient genome.
Agrobacterium
inserts a fragment of its own DNA into plant cells. Cells form a tumor like growth called crown gall.
-Agro effectively transformed dicots, but was not initially effective for monocots/some dicots.
The two major plant transformation methods
Agrobacterium, Biolistics (Microprojectile bombardment)
Biolistics
1.Gene gun
2. DNA of interest is coated in non reactive metal particles (gold or tungsten) and physically forced inside of plant cells at high velocity pressure.
(This has the potential to damage plant tissue).
input traits for better yields
insect resistance (BT)
Herbicidal Tolerance
Pathogen Resistance
Drought, cold, salt tolerance
Disease resistance
Output traits
improved nutritional content
-production of novel compounds
-reduced oxidation
Taq Polymerase
Enzyme capable of synthesizing new DNA strands, isolated from heat loving bacterium
Camv35s
promoter
NOS
Terminator
PCR Reaction
process in which a specific DNA region can be copied continuously, under a particular set of conditions.
Electrophoresis
technique used to separate DNA by size.
Plant hormones
organic compounds produced in small quantities that have variable impacts on growth, development, and life cycle events,
A plant growth regulator or PGR is…
any substance, natural, or synthetic thing applied to plants to modulate their growth and development.
eg. root hormones
The darwins
cut tips of plants to find if they react to light
The discovery of plant hormones
The observation of how plants move and grow in response to light direction, called phototropism, initiated a series of experiments over 50 years that led to the discovery of auxin.
Peter Boysen Jansen
established that a water-soluble chemical is responsible for moving thru the stem to induce the bending effect.
Frits Went
Isolated chemical and found that growth effects were inducible even without light.
Auxin
“to increase”
-Produced in seed embryos, buds, young flowers, SAMs
Major functions include:
1. Stimulate cell expansion all over the plant
2. Induces root growth + branching from pericycle
3. Promotes differentiation/specialization of vascular tissues.
4. Prevents axillary bud growth/branching near stem tips
(apical dominance)
Synthetic auxins
2-4-0,
stimulate growth in low concentrations but herbicidal in high concentrations.
How were gibberellins discovered
Foolish seedling disease of rice
Cytokinins
Produced in roots and germinating seeds
-transported to shoots via xylem
1. Promote cell division all over the plant
2. Delay aging and death of vegetative organs
3. Stimulate branching and shoot growth (negatively effected by auxin)
Giberellins
110 natural forms
1. Promote cell division and elongation in shoots especially at internodes
2. Stimulates flower and cone development
3. Application during flowering and young fruit development leads to larger fruits that are further apart (grapes)
senescence
aging and death
Abscisic acid
(ABA) The conservation hormone.
- found or produced in mature leaves, roots, fruits, seeds, BEFORE Germination
1. Induces and maintains seed dormancy (Blocks gibberellin activity)
2. Induce guard cells to close during periods of drought and heat.
3. Influences rate and amount of h2o and sugar transported to fruits and seeds.
Ethelyne
c2H4
-Single molecule (gaseous)
-Stress from damage and ripening causes Ethelyne to be released.
Produced in potentially all living tissues/cells
1. Can be applied to induce ripening
2. Injury/disturbance/stress results in production
3. stimulates senescence
4. Accumulates when plants encounter a physical barrier
How does water move upward through a plant against gravity?
loss of h2o leads to more absorption. The cohesive nature of water causes transpiration.
Transpiration
Loss of water vapor via stomata
-This cools the plant as water is released
-Maintains water movement and absorption in the plant.
What conditions result in higher transpiration rates?
heat, dryness, air movement over leaf surface
Water potential
Potential energy of water
1. Calculated by accounting for physical pressure of h2o concentration of solutes in cells.
Turgor pressure
Pressure that results from water absorption and accumulation in cells.
1. usually positive in living cells, where pressure is exerted against cell walls.
2. Negative pressure in dead cells
Tropisms
Growth response to directional stimulus
Phototropisms
Light, caused by differential cell elongation/expansion (induced by auxin) eg. plants bending towards light
Gravitropisms
shoots are negatively gravitropic(grow upwards)
etiolation
grown in the dark
Turgor movements
Chganges in water potential that dramatically increase or decrease turgor in specific tissues are responsible for a number of plant porgan movements.
eg. (venus flytrap)
eg. Mimosa leaves folding at touch)
Sleep movements
changes in turgor responsible for these
1. Shamrock fold their leaves at night
2. Mimosa leaves
ecology
study of organisms and interactions w/ their environment.
Biological communities
group of species w populations living in one area that have potential to interact chemically and or physically
the scope of ecology
1.population
species
ecosystem
landscape
***Communities
Basic properties of biological communities
- Diversity (organisms or species that compose it)
- Characteristic species (oak hickory forest)
- Trophic structure (feeding relationships)
- When disturbed will return to a similar composition over time.
Richness
number of different species present
sp1+sp2+sp3=sp(n)
density
number of individuals within a given area accounting for their physical footprint.
Relative abundance
number of individuals of a species compared to others present.
number of individuals in sp1/ #sp1+#sp2+#spn
diversity
unusually high richness with high relative abundance
sample plots
representative snapshots of composition that are indicative of the larger area
abiotic factors
wind
temp
precip.
soil
topography
elevation
light/radiation
ecosystems
communities plus abiotic factors
Biomes
largest in scale, based on climate plant composition and topopgraphy.
We live in what biome
temperate deciduous forest.
Threatened species
has the potential to become endangered within its growth range.
Endangered species
has potential to become extinct
Trophic Structure
feeding relationships
Producers
Photosynthesizers
Autotrophs, convert light to chemical energy
Consumers
obtain chemical energy through Heterotrophy
Calories
How we measure chemical energy
Biomass
Amount of living matter in an ecosystem.
primary productivity
The rate at which producers build biomass
Primary productivity is highest in
Algal beds/tropical rainforests
primary productivity is lowest in
desert, open ocean
Disturbance
damage to communities or ecosystems, at least temporarily, that may hinder or destroy organisms.
examples of disturbances
human activity
invasive species
disease
nat. disaster
pollution
Primary succession
occurs where there is no soil/ no previous plants/ no organic matter
ecological succession
ordered progression of change in a communities composition.
- progression from colonization to a climax community.
-
examples of primary succession
receding glaciers expose a rock face
-volcanic rock
-moss establishing on gardener hall roof
secondary succession
occurs where there is soil/previous plant communities that were disturbed.
examples of secondary succession
abandoned crop field
hurricane flood areas
climax communities
terminal group of species that dominate a community… end of succession.
