Question 1: The process of mineralization by microorganisms help in the release of:

• A. inorganic nutrients from humus.
• B. both organic and inorganic nutrients from detritus.
• C. organic nutrients from humus.
• D. inorganic nutrients from detritus and formation of humus.

Question 2: Analyse the following ecosystems and discuss, which will be more productive in terms of primary productivity: A young forest, a natural old forest, a shallow polluted lake.

Question 3: OR (B) Differentiate between Net primary productivity and Gross primary productivity in an ecosystem.

Question 4: (A) Identify the type of pyramid given below and write two identifying features of such a pyramid : [Diagram is implied but not provided in text]

Question 5: OR (B) (i) Construct an ideal pyramid of energy when $10,00,000$ Joules of sunlight is available.
(ii) Mention the energy obtained by the fourth level of this pyramid.

Question 6: Name the type of food chains responsible for the flow of larger fraction of energy in an aquatic ecosystem and a terrestrial ecosystem, respectively. Mention any two differences between the two food chains.

Question 7: **OR**
(i) What does an ecological pyramid represent?
(ii) The Ecological pyramids may have an 'upright' or an 'inverted' shape. Justify with the help of suitable examples.