The light environment of plants and photosynthetic adaptations

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REWM 3500 Rangeland Plant Ecophysiology Friday,
September 4, 2009
The light environment of plants and
photosynthetic adaptations

• Light response curve of photosynthesis
• Adaptation and acclimation to variable light
  conditions

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9.7 Response of photosynthesis to light in a C3
plant
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9.8 Light-response curves of photosynthetic
carbon fixation in sun and shade plants
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9.10 Light-response of photosynthesis of a sun
plant grown under sun or shade conditions
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9.11 Changes in photosynthesis in individual
needles, a complex shoot, and a forest canopy
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9.1 Leaf anatomy from a legume (Thermopsis
montana) grown in different light environments
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Sun
Shade
Upper palisade parenchyma
Lower palisade parenchyma
Spongy parenchyma
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Terms to know Light response curve Light
compensation point (LCP) Apparent light use
efficiency (phi, ?) initial slope Maximum rate
of photosynthesis - Amax Dark respiration
(Rd) Light limited part of curve Carboxylation
limited part of curve Sun and shade
leaves Palisade layer Spongy layer Grana
stacks Leaf level adaptation and acclimation