According to $David \ Tilman$,greater the diversity,greater is the primary productivity. Can you think of a very low diversity man-made ecosystem that has high productivity?

The following diagram shows the phosphorus cycle. Identify the producers in it.

Solar energy is converted into chemical energy by plants,and this chemical energy is converted into kinetic or heat energy in animals. This process demonstrates:

Carbon constitutes . . . . . . of dry weight of organisms and . . . . . . percentage is dissolved in oceans out of total global carbon.

Consider the following four statements $(A-D)$ and select the correct option stating which ones are true $(T)$ and which ones are false $(F)$.
Statements:
$(A)$ Vertical distribution of different species occupying different levels in a community is called stratification.
$(B)$ Net primary productivity minus respiration losses is the gross primary productivity.
$(C)$ Rate of biomass production is called decomposition.
$(D)$ Annual net primary productivity of oceans is $55$ billion tons.

Select the correct option for the following processes:
$P$ - Formation of organic components from inorganic components
$Q$ - Formation of inorganic components from organic components
Select the correct option for $P$ and $Q$.