Adaptations to photosynthesize in sun and shade
| Shade plant | Sun plant |
| 1. Abundant chlorophyll b (low chlorophyll a to chlorophyll b ratio) which gives leaves dark green colour to increase light absorption in the dark; | 1. Abundant chlorophyll a (high chlorophyll a to chlorophyll b ratio) to increase light absorption;
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| 2. Palisade/ spongy mesophyll ratio low to allow maximum light penetration; | 2. Palisade/ spongy mesophyll ratio high to minimise light penetration; |
| 3. Mesophyll cell surface / leaf area ratio low to maximise light trapping; | 3. Mesophyll cell surface / leaf area ratio high to minimize excessive light and transpiration; |
| 4. Leaf orientation horizontal to maximize light trapping; | 4. Leaf orientation erect to minimize light trapping; |
| 5. Reddish leaf undersides to enhance reflectance back up through the photosynthetic tissue; giving the plant a second chance to utilize the light. | 5. Stomatal density high to avoid over heating;
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| 6. Stomatal density low to avoid over cooling;
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6. Much carotenoids to prevent damage to chlorophyll from very bright light. |
| 7. Thin leaves to maximise light penetration;
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7. Thick leaves to minimise light penetration;
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| 8. Stomatal size large to allow loss of excess water;
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8. Stomatal size small to minimise water loss; |
| 9. Elongated internodes for increased access to light;
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Other features (i) RuBISCO and soluble protein content /mass higher (ii) Chlorophyll / soluble protein ratio high (iii) Chloroplast size small |
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Dr. Bbosa Science
CATEGORIES General
TAGS Dr. Bbosa Science
