may also be produced in seeds * transported from leaves via phloem * known effects on plant development - slows growth (prepares plant for dormant period) - stimulates seed dormancy (prevents premature seed germination from occurring) - stimulates production of seed storage proteins - stimulates closing of stomata in most plant species (causes K+ loss in guard cells) Ethylene * a gaseous hormone - unusual * because its a gas, ethylene can move via diffusion from region of synthesis to target region - air spaces between cells * synthesized in most plant tissues in association with fruit maturation or leak abscission * known effects on plant development - stimulates fruit ripening - leaf and flower senescence - leaf and fruit abscision * autumn colors - combined result of the following - production of chlorophyll ceases - specific non-chlorophyll pigments are produced - aready presented pigments no longer conceeled by chlorophyll
(seeds; transported; from leaves) (cells; synthesized; L:in most plant tissues in association) (autumn colors - combined result of the following - production of chlorophyll ceases - specific non-chlorophyll pigments are produced - aready presented pigments; conceeled; by chlorophyll; T:no longer) (ethylene; can move; from region of synthesis; to target region - air spaces between cells) (ethylene; to target; region - air spaces between cells)
seeds cells autumn colors - combined result of the following - production of chlorophyll ceases - specific non-chlorophyll pigments are produced - aready presented pigments ethylene ethylene
transported synthesized conceeled can move to target
from leaves
L:in most plant tissues in association
by chlorophyll T:no longer
from region of synthesis to target region - air spaces between cells
region - air spaces between cells