Plant Tropisms and Responses Glossary (Copy)
Tropisms are how plants make use of the 5 things that every living thing needs to thrive— sun, water, air, nutrients, and love.
Phototropism: Growth toward light; helps maximize photosynthesis.
Heliotropism: Tracking the sun’s movement across the sky (e.g., sunflowers).
Hydrotropism: Roots grow toward water sources.
Gravitropism: Roots grow downward (positive) and shoots upward (negative) in response to gravity.
Thigmotropism: Growth in response to touch; vines wrapping around supports.
Chemotropism: Growth toward or away from chemicals (e.g., pollen tube toward ovule signals.) Aerotropism: Growth response to oxygen availability.
Thermotropism: Growth in response to temperature changes.
Nyctinasty: Daily leaf movements responding to light/dark cycles (e.g., prayer plants).
