1. Nutrients are never lost from the ecosystems and are recycled. Write about
a) Gaseous cycle
b) Sedimentary cycle (Scores:1+1)
2. On earth, life exists even in extreme and harsh conditions. Mention any two major biomes in India. (Score: 1)
3. Ecological pyramids are usually upright. Meanwhile some, pyramid of biomass is inverted. Explain the reason. (Scores: 2)
1. (a) Biogeochemical cycle is an important phenomenon in very ecosystem. Describe phosphorus cycle. (Scores: 3)
(b) The plant communities in a given area show successive changes. Mention the stages of succession in a xerosere.
2. Earthworms are commonly referred as farmers’ friends. Deﬁne fragmentation. (Score 1)
1. The different stages of primary succession in water are represented below. Fill the gaps that are unﬁlled.
(c) Submerged free ﬂoating plant stage
(f) Shrub stage
(g) …………….. (Scores: ½ X 4 = 2)
2. An ecosystem consists of the following population:
Draw a food chain denoting each trophic level. (Scores: ½ X 4 = 2)
1. The products of ecosystem processes are named as ecosystem services. list out any four such services.
2. Pyramid of energy is never been inverted. Why?