PB 200 Final Exam

Describe microprojectile bombardment and its benefits and drawbacks.

uses "gene gun" DNA of interest is coated in non-reactive metal particles (gold) and physically force inside of plant cells at high velocity using gas pressure. Benefits: faster, chloroplasts DNA, monocot & dicots. Drawbacks: success rate low, expensive.

Define turgor pressure.

usually in living cells. results from water absorption into cells or movement of water from one cell to another. *venus flytrap *twining *mimosa leaves closing and folding*

define invasive

usually non-native, very fast repro rate, no natural predators

Short-day plants

will not flower unless night length is longer than critical period. (mums, poinsettia, gardenia)

Long-day plants

will not flower unless night length is shorter than a critical period. (snapdragons, hosts, sunflower.)

What plants have these methods been used on?

corn, potato, rice, sweet potato, wheat, cotton

day-neutral plants

flower irrespective of day length. (tropical grasses, tomatoes, petunias)

what is aerobic respiration?

glucose + oxygen = carbon dioxide + water produces 36 ATP

what is fermentation?

glucose= carbon dioxide + ethanol produces 2 ATP sugarcane-rum, blue agave-tequila, corn-whiskey

what is biological community?

group of species populations in one area that have the potential to physically and chemically interact.

Loss of plant biodiversity

habitat destruction (pollution, deforestation), invasive species, overcollecting.

describe alkaloids.

high pH 8-10. produced in 25% of all plant species. often bitter. caffeine, atropine- pupil dilation, opiates (morphine, codeine, papaverine.)- analgesics/depressants, cocaine- stimulant & anaesthetic, coniine- motor neuron inhibitor, mescaline- peyote cactus- psychoactive.

Describe agrobacterium and its benefits and drawbacks.

it inserts a fragment of its DNA into plant cells. this induces the plant to produce hormones that promote cell division. *put gene in agrobacterium. put agrobacterium in plant. agrobacterium carries gene.* Benefits: success rate is higher and its cheaper. Drawback: doesn't work on monocots.

what are the human uses of specialized metabolites? what are the plant functions of metabolites?

medicine, poison, flavor, nutrition, color for humans. attractants, defense, protection for plants.

define secondary succession.

occurs where there is soil, previous plant community that was disturbed. (abandoned field, hurricane floods, forest fired, brickyard.)

what are the major groups of plant specialized metabolites?

phenolics, terpenoids, alkaloids

what does is mean to be a transgenic plant? what are the benefits?

plants in which DNA from another species (with which the plant could not cross with) has been integrated. this allows for gene isolation and more precise results. delivery and incorporation of DNA.

define threatened.

potential to become endangered throughout most or all of its growth range

define endangered.

potential to become extinct throughout most or all of its growth range

Where are gibberellins produced and what do they do?

produce in: seed embryos, young shoots, root tips developing flowers. 1. primary growth of shoots by promoting cell division & elongation- works best w/auxins. 2. stimulate germination 3.stimulates flowering/cone development 4. application during early fruit development- larger fruits spaced further apart. (seedless grapes)

where is abscisic acid produced and what does it do?

produced in: mature leaves, roots, fruits, seeds, before germination 1. induces and maintains seed dormancy 2. high levels accumulate during drought stress- induce guard cells to close stomata 3. influences rate of water and sugar movement into fruits and seeds.

Where are cytokinins produced and what do they do?

produced in: roots tips and germinating seeds 1. cell division all over plant- especially in axillary buds. 2. stimulates shoot production- primary and secondary 3. delays aging and death of vegetative organs and cut flowers.

Where is auxin produced and what does it do?

produced in: shoot apical meristem, young, and bud. 1. stimulate cell expansion all over plant. 2. induce root primary growth and root branching 3. promote/ stimulate root production on cuttings and vines 4. promotes development of vascular tissue 5. inhibits axillary bud growth and branching in stems (maintains apical dominance.)

where is ethylene produced and what does it do?

produced in: tissues undergoing ripening/aging/death 1. bruising/injury/disturbance causes production 2. induces fruit ripening-can be applied to some fruits to continue ripening 3. stimulate leaf and fruit drop 4. accumulate in response to physical stress- especially in roots as they encounter barriers in soil.

primary productivity. where is it highest and lowest?

rate at which produces build biomass. high- algal beds/tropical rain forests. low-open ocean/desert scrub

what is ecology?

study of organism interactions w/their environment & each other.

what plants have been used as biofuels?

switchgrass- cellulose; produces 5x energy required to grow it- ethanol. miscanthus- grows fast; low nutrient requirement, large yield, C4. Arundo donax, sweet potato, wood chips, freeze tolerant eucalyptus, sugarcane.

Name two transformation methods.

agrobacterium, micro projectile bombardment.

what other technologies are being developed?

insect resistance, herbicide tolerance, golden rice, chestnut blight resistance.

define disturbance

damage to communities or ecosystems that may hinder or destroy organisms and/or alter resource availability. (fire, lightning, hurricanes, tornadoes, pollution)

who discovered plant hormones?

darwin & darwin- growth dependent on light being perceived by the tip of the shoot. Boysen-Jensen- determined chemical at tip is responsible- auxin.

describe terpenoids.

defense or attraction. -pine and cedar scent. -essential oils. -natural rubber -accessory pigments (carotenoids) -taxol (chemo) -artemisinin ( antimalarial drug)

properties of a biological community?

diversity, characteristic species- usually prominent or notable b/c of frequency of occurrence, trophic structure, when disturbed, will return to a similar composition.

describe phenolics.

include: lignin, tannins, anthocyanin (colors in flowers and fruits and leaves), salicylic acid (willow bark), urushiol (poison ivy), allelopathic chemicals (prevents growth of other plants nearby. walnut trees)

Define richness

number of difference species present

Define relative abundance

number of individuals of a species compared to other species present.

Define density.

number of individuals within a given area and /or accounting for their physical footprint

define primary succession

occurs where there is no soil or previous plants . (cliff face, roof top, volcanic rock.)