Adaptations to photosynthesize in sun and shade

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;

 

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;

 

6. Stomatal density low to avoid over cooling;

 

6. Much carotenoids to prevent damage to chlorophyll from very bright light.
7. Thin leaves to maximise light penetration;

 

7. Thick leaves to minimise light penetration;

 

8. Stomatal size large to allow loss of excess water;

 

8. Stomatal size small to minimise water loss;
9. Elongated internodes for increased access to light;

 

Other features (i) RuBISCO and soluble protein content /mass higher (ii) Chlorophyll / soluble protein ratio high (iii) Chloroplast size small

Please find free downloadable notes, exams and marking guides of agriculture, biology, and chemistry from digitalteachers.co.ug website.

Dr. Bbosa Science

CATEGORIES
TAGS
Share This

COMMENTS

Wordpress (0)
Disqus (0 )