Plant Signaling Flashcards
What is de-etiolation?
Greening
Auxins: production site and action
Site: Shoot meristem/young leaves
Action: Stem elongation
Cytokinins
Site: Roots
Action: Cell division
Gibberellins
Site: Meristems, leaves and seed
Action: Stem elongation and reproduction
Brassinosteroids
Site: All plant tissues
Action: Cell division, xylem differentiation
Abscisic acid
Site: All plant tissues
Action: Inhibits growth, promotes dormancy
Ethylene
Site: All plant tissues
Action: Fruit ripening and plant senescence, triple response
Phototropism
Movement or growth of a plant in response to unidirectional light (e.g., heliotropism by sunflowers)
Gravitropism
Movement or growth of a plant in response to gravity
Thigmotropism
Movement or growth of a plant in response to contact with an object
Thigmonasty
Plant folds when touched in a unidirectional manner
Nastic movement
Reversible or temporary movements in response to a stimulus (regardless of stimulus direction)
Circadian rhythm
A 24-hour cycle of response in plants
Phytochrome
A blue-green pigment that exists in two forms and signals the light switch in de-etiolation
Vernalization
Refers to a low-temperature stimulation of flowering (stratification in seeds is similar)
Statoliths
Amyloplasts that move in the plant root and shoot tip to help in responding to gravity
Triple Response
The slowed elongation, thickening and turning of an underground shoot in response to an obstacle
