AP BIOLOGY

Detailed explanation-1: -Net productivity = the organic materials that remain after photosynthetic organisms in the ecosystem have used some of these compounds for their cellular energy needs (cellular respiration) So the correct option is ‘rate of energy production per unit area over a time period during photosynthesis’

Detailed explanation-2: -These organisms are known as autotrophs, since they can use inorganic substrates and solar energy to carry out metabolic processes and build cellular material. Primary productivity due to photosynthesis is commonly measured by quantifying oxygen production or CO2 assimilation.

Detailed explanation-3: -Carbon dioxide plays an important role in photosynthesis. Plants use energy from light to split water molecules; they then use carbon dioxide to synthesize carbohydrates.

Detailed explanation-4: -Definition. The amount of carbon retained in an ecosystem (increase in biomass); it is equal to the difference between the amount of carbon produced through photosynthesis (GPP) and the amount of energy that is used for respiration (R).

Detailed explanation-5: -Net primary production (NPP) is the amount of biomass or carbon produced by primary producers per unit area and time, obtained by subtracting plant respiratory costs (Rp) from gross primary productivity (GPP) or total photosynthesis.