The surface of water in a lake appears green due to a layer of tiny free-floating organisms X on its surface. The lake water also contains organisms like water beetle, fish and tadpole. The sun shines over the lake water and provides energy for the functioning of this lake ecosystem.
(a) What could organisms X be ?
(b) Write a food chain comprising of all the four organisms metioned.
(c) What is the general name of the food chains like the one written above ?
(d) Name (i) secondary consumer (ii) producer (iii) tertiary consumer, and (iv) primary consumer, in the above food chain.
(e) If the tertiary consumer gets 0.2 J of energy from the secondary consumer, then how much energy was radiated by the sun to the producer ?

Answer

(a) Algae (b) Algae `to` Tadpole `to` Water beetle `to` Fish (c) Aquatic food chains (d) (i) Water beetle (ii) Algae (iii) Fish (iv) Tadpole (e) 20000 J