noun
phototropism
foh-toh-TROH-piz-um/ˌfəʊtəʊˈtrəʊpɪzəm/
Directional growth of an organism toward or away from light.
A seedling shows phototropism as its stem grows toward light.
Etymology
Tropism names an organism’s tendency to turn or move in response to a stimulus. Adding ‘light’ identifies the stimulus that directs its growth or movement.
In context
about uh movement or tropism and how light affects that movement or that growth and what you can see in the picture down below is a perfect illustration of how phototropism works
More examples
- Growth away from a light source is called negative phototropism.
- The students measure phototropism by lighting seedlings from one side.
- Phototropism makes the shoot bend toward the lamp as it grows.
Forms
phototropism
phototropic adjective — Growing toward or away from light.
Similar words
- tropism
- Broader term for directional growth responses to light or other stimuli.
- heliotropism
- Specifically follows the sun, sometimes through movement rather than growth.