BIO205H5 Chapter Notes - Chapter 6: Vascular Bundle, Rubisco, Leaf
Document Summary
6. 8 constraints imposed by the physical environment have resulted in a wide array of plant adaptations. Many features of the physical environment directly influence plant process are interdependent. 6. 9 species of plants are adapted to different light environments. Plants live in two qualitatively different light environments. Shade: less photosynthetic enzyme rubisco, more chlorophyll, lower light saturation point and maximum rate of photosynthesis, lower leaf respiration. Specific leaf area (sla) is the ratio of surface area to weight. Lower light conditions produces greater sla, and thinner leaves. Dramatically reduced survival and growth rate in shaded conditions. Little difference in survival and growth rates under sunlight and shade conditions. Limited rate of growth even in high-light environments. 6. 10 the link between water demand and temperature influences plant adaptions. Leaf curing and wilting allows reduced water loss and heat gain, dropping leaves before drought season. C4 plants increase water-use efficiency in warm, dry environments, using mesophyll and bundle sheath cells.
