Plants & CreaturesGreek → English
Phototropism
/foʊˈtɒtrəpɪzəm/noun
The growth of a plant towards or away from a light source.
The Greek roots
φῶς, φωτός
phôs, phōtós
light
τροπή
tropḗ
a turning
Literally: “turning by light”
The story of the word
Darwin and his son Francis worked out the mechanism in 1880 by capping seedling tips with tiny foil hoods: the tip senses the light, the bending happens below it. That experiment led to the discovery of auxin, the hormone that pools on the shaded side and stretches those cells longer. The τροπή in the name is the same turning as in the tropics, the latitudes where the sun turns back.
- How it travelled
- Ancient Greek → scientific coinage → English
- First recorded
- 19th century
Same family
photographphotosynthesisgeotropismtropic
In a sentence
Rotate the pot every few days or phototropism will leave you with a lopsided basil plant.