Name the first trophic level of a detritus food chain. How is it different from first trophic level of GFC?

Why the length of a food chain in an ecosystem is generally limited to 3-4 trophic levels?

Why Phosphorus cycle is called an imperfect cycle, while Carbon and Nitrogen cycle are perfect?

Two groups of students performed an experiment to find out the biomass of 50 plants of a species. Group A first dried the plants and then measured the weight, while Group B measured weight with fresh plants.
i) Whose method is more correct?
ii) Why?
iii) What term is used to denote mass of living material at a particular time in a trophic level?

(a) All the tigers at Sariska reserved forest have died . What will be the long term effect of this on the population of deer in that forest.
(b) Now three tigers have been brought there from outside. What difference will it make?

From thousands of years, balance was maintained between the amount of CO₂ and O₂ in the atmosphere. But recently it has been observed that amount of CO₂ has increased than normal?
i) What is the reason for it?
ii) What will be its possible effect on life on earth?

During a visit, students found that a forest has been destroyed totally by fire.The students asked their teacher, “Can the forest grow here again?” The teacher explained,” Yes, of course. Even a bare rock in course of time can also convert into a forest.  Growth of forest  on a bare rock is known as primary succession while community developed in the burnt forest is known secondary succession."
i) In your opinion, where will be the growth of community faster the burnt forest or the bare rock? Why?
ii) Why on bare rock succession is called primary while in a burnt forest, succession is secondary?

Vultures feed on dead animals.  Earthworms feed on dead leaves, while Bacteria also feed on dead plants and animals. How can you differentiate the above mentioned organisms? What is the position of above mentioned organisms in a food chain?

A large number (about 1000) of insects are feeding on a tree, while a number of 100 small birds depend on the insects and are in turn eaten by 10 large birds. Draw an ecological pyramid. Also draw ecological pyramid of energy for the same data?

Try to Make ecological pyramid of a food web. What difficulties do you face in making it?