UPSC 2013 › Environment & Ecology › Ecosystems & Ecology Concepts

In the grasslands, trees do not replace the grasses as a part of an ecological succession because of

Which one of the following is the correct sequence of ecosystems in the order of decreasing productivity?

With reference to food chains in ecosystems, consider the following statements:

1. A food chain illustrates the order in which a chain of organisms feed upon each other.
2. Food chains are found within the populations of a species.
3. A food chain illustrates the numbers of each organism which are eaten by others.

Which of the statements given above is/are correct?

Which one of the following terms describes not only the physical space occupied by an organism, but also its functional role in the community of organisms?

With reference to the food chains in ecosystems, which of the following kinds of organism is/are known as decomposer organism/organisms?

1. Virus
2. Fungi
3. Bacteria

Select the correct answer using the codes given below.

Which of the following is/are unique characteristic/characteristics of equatorial forests?

1. Presence of tall, closely set trees with crowns forming a continuous canopy
2. Coexistence of a large number of species
3. Presence of numerous varieties of epiphytes

Select the correct answer using the codes given below.

Which of the following leaf modifications occurs/occur in desert areas to inhibit water loss?

1. Hard and waxy leaves
2. Tiny leaves or no leaves
3. Thorns instead of leaves

Select the correct answer using the codes given below.