1. SI session Growth Regulators Topic 27, 28 Spring 2010
Biology
SI session
Growth Regulators
Topic 27, 28
Spring 2010
Dr. Hughey’s Bio 3 (Lab.)
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Growth factors
Internal factor
External factor
Plant Hormones
Light, Temperature, Gravity, Day length…etc
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Auxin
-Plant Hormones
-IAA(Indoleacetic acid)
-Produced in _______
-________________
(remains dormant)
shoot tip Leaf primordia, young leaves, developing seeds
Inhibit axillary buds
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Auxin - Inhibit axillary buds
(remains dormant)
Apical Dominance
_______________
-By hormone _____
-inhibitory influence of the apical bud upon lateral buds.
Auxin
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In the experiment of Apical Dominance
lanolin
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Auxin promotes the formation of __________________________.
Lateral and Adventitious Roots
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Auxin prevents Abscission(leaf drop).
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Auxin promotes cell elongation in shoot.
Auxin inhibits cell elongation in root.
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Auxin inhibits cell elongation in root.
Auxin promotes cell elongation in shoot.
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_________
:jointlike thickening at the base of the petiole or petiolule.
facilitates __________ movements
e.g
Pulvinus
nyctinastic
Nyctinasty, Thigmonasty
Pulvinar movement
-caused by changes in _____________ leading to a contraction or expansion of the parenchyma tissue.
turgor pressure
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Tropism
_______ - directional growth in response to an external stimulus.
___________ : the curving of a growing shoot toward light.
Phototropism
_____________ - the response to contact with a solid object.
Thigmotropism
____________- the orientation of leaves and flowers to the sun.
Heliotropism
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Phototropism
___________ - the curving of a growing shoot toward light.
- In theory, cell elongation by the hormone: __________
Auxin
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____________- the orientation of leaves and flowers to the sun.
Heliotropism
-by turgor pressure changes of the ________
pulvinus
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15. Thigmomorphogenesis- the alteration of plant growth patterns in response to mechanical stimuli.
From Dr. Hughey’s Bio3 class slide