Intro to PGR and Plant Horomones Flashcards
What is a Plant Hormone?
Organic chemical messenger that is produced in one location of the plant but controls processes throughout the plant like: • Most cellular division and elongation • Pattern formation • Organ formation • Sex determination • Reproductive cycles • Seed germination
What is the difference between phototropism and gravitropism? What is the chemical involved?
Phototropism - plant growth towards a light source Gravitropism - Plant growth towards the direction of gravity.
- Auxin is the chemical involved.
Auxin….What does it do?
-Inhibits the growth of tillers, promotes apical dominance. -Maintains active root growth
Cytokinin….What does it do?
-Promotes Lateral shoot growth and Inhibits root growth. -Opposite of Auxin
What is the main function of Gibberellins in a plant?
Cell elongation. Makes the plants tall/long. Induces seed germination and makes plants flower faster.
What does ABA do?
ABA induces stomal closure. It promotes plants to become more drought resistant by decreasing transpiration.
What happens to a plant when it is exposed to high concentrations of ethylene?
• Stunted growth • Thick stems • Leaf yellowing • Leaf abscission
Define Epinasty:
Downward curvature of branches or leaf petioles
Absisic Acid is directly related to :
Water Loss in plants
What is 2-4D
A selective herbicide used to kill broadleaf weeds
What processes do plant hormones affect?
Most cellular activities including: -cellular division, elongation and differentiation. -Patter formations -Organ formation -Reproductive cycles -Seed germination -Stress responses
Auxin was first described by who?
Charles Darwin
In relation to a light source, where does Auxin accumulate?
Opposite the light source
What Cehmical Promotes Lateral shoot growth and Inhibits root growth?
Cytokinin
What Chemical -Inhibits the growth of tillers, promotes apical dominance. -Maintains active root growth
Auxin
