Which of the following is most likely to exhibit the maximum difference between GPP and NPP?
1. phytoplankton in the ocean.
2. corn plants in a farmerʹs field.
3. prairie grasses.
4. an oak tree in a forest.

Primary producers near deep-sea vents are:
1. Chemohetrotrophic prokaryotes
2. Chemoauotrophic prokaryotes
3. Photosynthetic prokaryotes
4. Photosynthetic autotrophs

Identify the incorrectly matched pair:
1. Carnivores -- secondary or tertiary consumer
2. Decomposers -- microbial heterotrophs
3. Herbivores -- primary consumer
4. Omnivores -- molds, yeasts and mushrooms

Decomposers like fungi and bacteria are :

Choose the correct answer :

The process of mineralization by micro-organisms helps in the release of:

Productivity is the rate of production of biomass expressed in terms of :
i. $(\mathrm{kcal} {\mathrm{m}}^{-3}) {\mathrm{yr}}^{-1}$
ii. $\mathrm{g} {\mathrm{m}}^{-2} {\mathrm{yr}}^{-1}$
iii. $\mathrm{g} {\mathrm{m}}^{-1} {\mathrm{yr}}^{-1}$
iv. $(\mathrm{kcal} {\mathrm{m}}^{-2}) {\mathrm{yr}}^{-1}$

An inverted pyramid of biomass can be found in which ecosystem?

Which of the following is not a producer?

Which of the following ecosystems is most productive in terms of net primary production? 

Pyramid of numbers is :
1. Always upright
2. Always inverted
3. Either upright or inverted
4. Neither upright nor inverted