phototropism
Sunward stem bending
Phototropism is the tendency of plants to grow toward or away from light.
A houseplant bending toward a window demonstrates positive phototropism—the stems and leaves orient themselves to maximize light exposure.
Roots growing away from light show negative phototropism.
The seedlings exhibited strong phototropism within days of sprouting.
Plant gravity response
- photomorphogenesisPlant growth shaped by illumination
- stimulusWhat prompts a reaction
- responseAnswer to stimulus
- directionalIndicating a path
positive · negative · orientation · adaptive
Plant growth hormone
Light-harvesting plant pigment
- leavesTree's photosynthetic organs
- stemsPlant's main axes
- seedlingsNewly germinated plants
- shootsFires or photographs
sunflower · houseplants · etiolation · canopy · vine · tendril · cotyledon · flora
Radiance from our star
- illuminationProvision of light
- daylightSun's natural glow
- solarOf the star
- radiationEnergy propagation through space
wavelength · intensity · spectrum · UV
gravitropism
Plant gravity response
- photomorphogenesisPlant growth shaped by illumination
- stimulusWhat prompts a reaction
- responseAnswer to stimulus
directional · positive · negative · orientation · adaptive
auxin
Plant growth hormone
chlorophyll
Light-harvesting plant pigment
shoots · sunflower · houseplants · etiolation · canopy · vine · tendril · cotyledon · flora · autotroph
sunlight
Radiance from our star
- illuminationProvision of light
- daylightSun's natural glow
- solarOf the star
radiation · wavelength · intensity · spectrum · UV