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Glite Dictionary
phototaxis

phototaxis

1 8.5
Movement of a living thing toward or away from light
  • noun
  • /ˌfoʊtəˈtæksɪs/
  • Specialized
: fototaxia
  • Many plants demonstrate phototaxis by growing towards the sunlight for optimal photosynthesis.

Examples

  • But there are some cells that also exhibit negative phototaxis that move on on that same scale.

  • The larvae of certain aquatic insects show phototaxis as they swim towards the brighter areas of the water.

  • Some microorganisms rely on phototaxis to navigate towards light sources vital for their energy needs.

Surface Forms

phototaxis singular
phototaxes plural

Morphology

phototaxis = taxis (semi-transparent) = photo + taxis

The term is built compositionally from 'photo-' meaning light and 'taxis' meaning directed movement, but 'taxis' is a specialized combining form that many learners will not know.

Etymology

Phototaxis comes from the parts photo- meaning 'light' and -taxis meaning 'movement'. Think of photo- as in photograph to remember 'light', so phototaxis is when a living thing moves toward or away from a light source.