Blackman's Law of Limiting Factors — NEET Biology
📚 Practice ConceptWhen several factors affect any [bio] chemical process, Blackman's (1905) Law of Limiting Factors comes into effect. This states the following:
Consider the following statements : 1. Blackman’s law of limiting factors states that the rate of photosynthesis depends on the single factor present in the highest concentration. 2. Very high light intensity may cause photooxidation of chlorophyll, damaging the photosynthetic apparatus. 3. Beyond light saturation point, further increase in light does not enhance photosynthesis if CO₂ is limiting. 4. In aquatic plants, light penetration is an important factor for photosynthetic rate. 5. Water is never a direct limiting factor, but drought leads to stomatal closure and reduced CO₂ entry.
View solution & NCERT explanation
Correct answer: D — 2, 3, 4 and 5 are correct
Statement 1: Wrong — Blackman’s law says rate is determined by the most limiting factor, not the one in highest concentration. Statement 2 : High light → photooxidation of chlorophyll damages photosynthetic apparatus. Statement 3 : Beyond light saturation, increase in light has no effect if CO₂ is limiting. Statement 4 : In aquatic plants, light penetration is key for photosynthesis. Statement 5: Water does not directly limit photosynthesis but in drought stomata close, reducing CO₂ availability.
What does NCERT say about When several factors affect?
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