Neet Solved Paper 2015 Question 45

Question: In an ecosystem the rate of production of organic matter during photosynthesis is termed as

Options:

A) net primary productivity

B) gross primary productivity

C) secondary productivity

D) net productivity

Show Answer

Answer:

Correct Answer: B

Solution:

  • The rate of production of organic matter (chemical energy) as biomass that primary producers (via photosynthesis) created in a given duration of time is called Gross Primary Productivity (GPP). Net primary production is the rate at which all plants (producers) in an ecosystem produce net useful chemical energy, it is equal to difference between the rate at which plants in an ecosystem produce useful chemical energy (GPP) and the rate at which they use some of that energy during respiration. NPP = GPP-respiration (by plants) Secondary productivity is the generation of biomass or organic matter by heterotrophic (consumers) in a system. Net productivity is the amount of energy trapped in organic matter during a specific interval at a given trophic level less than that lost by the respiration of the organisms at that level.