Biology · Ecosystems · NEET
Productivity is the rate of biomass production. This is the exact NCERT definition. It tells you how fast an ecosystem produces new organic matter (living material). Because it is a rate, it is always measured per unit area and per unit time, for example g m-2 yr-1.
No. Biomass is the total amount of organic matter present at one moment (a standing amount, like g m-2). Productivity is the RATE at which that biomass is made, so it needs a time term (like g m-2 yr-1). NEET often traps students here: a value without a per-year term is biomass or production, not productivity.
Productivity is divided into primary productivity and secondary productivity. Primary productivity is made by producers (plants) and is further split into Gross Primary Productivity (GPP) and Net Primary Productivity (NPP). Secondary productivity is the rate of formation of new organic matter by consumers (heterotrophs).
Because productivity is a RATE, not a total. A rate always describes an amount per time. That is why NCERT expresses it as g m-2 yr-1 or (kcal m-2) yr-1. This one point is directly asked in NEET, so remember: no time term means it is NOT productivity.
Primary productivity is the rate at which producers (autotrophs) make organic matter using photosynthesis. Secondary productivity is the rate at which consumers (heterotrophs) form new organic matter from the food they eat. Both are rates of biomass production, but by different organisms.
Which of the following is the unit of productivity of an Ecosystem?
Match List I with List II: A. Productivity B. Net primary productivity C. Gross primary productivity D. Secondary productivity; I. GPP minus respiration losses II. Rate of formation of new organic matter by consumers III. Rate of biomass production IV. Rate of production of organic matter during photosynthesis.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Productivity is the rate of biomass production in an ecosystem. This is the exact NCERT line and is the safest answer to write in NEET.
It is expressed as g m-2 yr-1 or (kcal m-2) yr-1. The time term (yr-1) is essential because productivity is a rate.
Primary productivity (by producers/plants) and secondary productivity (by consumers). Primary productivity is further divided into GPP and NPP.
It is the input of energy and organic matter into the ecosystem. All food chains, energy flow, and consumer growth depend on how much producers make first.
Yes. NCERT states primary productivity depends on the plant species inhabiting a particular area, plus environmental factors, nutrients, and the photosynthetic capacity of the plants.
