Question

Given below is a phosphorus cycle. Select the incorrect statements from the following.


(i) It represents phosphorus cycling in an aquatic ecosystem.
(ii) It represents phosphorus cycling in a terrestrial ecosystem.
(iii) The natural reservoir of phosphorus is forest rocks.
(iv) There is a respiratory release of phosphorus into the atmosphere.
(v) Gaseous exchange of phosphorus between organisms and the environment does not occur.

• A. (i), (ii) and (v)
• B. (i), (iii) and (iv)
• C. (ii), (iii) and (iv)
• D. (i), (iii), (iv) and (v)

Answer 1

Answer: (B)

The flow chart represents phosphorus cycling in a terrestrial ecosystem because phosphorus cycle is a sedimentary cycle and its reservoir pool is lithosphere. Rocks are the natural reservoir of phosphorus, in the form of insoluble ferric and calcium phosphate. When rocks are weathered, minute amounts of these phosphates dissolve in the soil solution and these inorganic phosphates $\left(P O_{4}^{3 -} , H P O_{4}^{2 -} , \, \, o r \, H_{2} P O_{4}\right)$ are absorbed by plants from the soil and water bodies and eventually pass into animals through food chains. There is no respiratory release of phosphorus between organisms and environment are negligible.