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photopositive

Line breaks: photo|posi¦tive
Pronunciation: /ˌfəʊtəʊˈpɒzɪtɪv
 
/

Definition of photopositive in English:

adjective

1 Biology (Of an organism) tending to move towards light.
Example sentences
  • The frequency of lethal and semilethal chromosomes in the photopositive population was 43%, and those for the photonegative and the unselected populations were 18% and 27%.
  • At higher temperatures D. pseudoobscura, D. simulans, and D. melanogaster become more photopositive, while D. ananassae and D. willistoni become less photopositive.
2 Physics (Of a substance) exhibiting an increase in electrical conductivity under illumination.
Example sentences
  • Most maskants are photopositive materials and are designed to operate at low pH and to be developed (or stripped) in high pH solvents.
  • When a photopositive material is used, the photosensitive material situated on the active sensor surface is exposed, while the remaining photosensitive material remains unexposed.

Definition of photopositive in:

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Word of the day prepotent
Pronunciation: prɪˈpəʊt(ə)nt
adjective
greater than others in power or influence