[" (d) Organisms which depend on the producers etther alirectly or indirectly tor tood "],[" 19.Write the common food chain of a pond ecosystem."]

What is a food chain ? Write the common food chain of a pond ecosystem .

Write one or two words for each of the following statements/definitions : (a) Each level of food chain where transfer of energy takes place (b) The physical factors like temperature, rainfall, light, soil, air and water of an ecosystem (c) Organisms which depend on the producers for food either directly or indirectly (d) The physical and biological world where we live in (e) Selfcontained unit of living things and their non-living environment needing only sunlight for its functioning

(a) State one advantage of using jute bags over plastic bags for shopping. (b) Write a common food chain of a pond ecosystem having four links.