light intensity
What light intensity means in Biology GCSE, as defined for AQA, OCR.
Definitions of light intensity
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Reference: OCR
Increasing this supplies more radiant energy to excite electrons in chlorophyll, raising the rate proportionally until another factor limits.
Relative intensity is a ratio calculated using 1 / d², so it is dimensionless or given in arbitrary units, never cm⁻².
Supplies the energy for photosynthesis, so it affects plant growth and the food available to consumers.
A quantity that decreases with distance from a lamp because the light spreads out over a larger area.
Changed by moving a lamp to different measured distances from the pondweed.
Topics that use light intensity
- Abiotic factors (AQA GCSE)
- Rate of photosynthesis (AQA GCSE)
- Photosynthesis (OCR GCSE)
Related terms
- graph interpretation
- inverse square law
- limiting factor
- limiting factors
- abiotic factors
- axis scaling
- Biomass
- bubble counting
Using light intensity in the exam
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