(a) Colonization of a rocky terrain is a natural process. Mention the group of organisms which invade this area first. Give an example.

(b) Over the years, it has been observed that some of the lakes are disappearing due to urbanization. In absence of human interference, depict by making a flow chart, how do the successional seres progress from hydric to mesic condition.

(c) Identify the climax community of hydrarch and xerarch succession.

The graph given below shows the variation in the levels of ovarian hormones during various phases of menstrual cycle:

(a) Identify ‘A’ and ‘B’.

(b) Specify the source of the hormone marked in the diagram.

(c) Reason out why A peaks before B.

(d) Compare the role of A and B.

(e) Under which condition will the level of B continue to remain high on the 28^thday?

Explain the process of protein synthesis from processed mRNA.

Which methodology is used while sequencing the total DNA from a cell? Explain it in detail.

Taking the example of a lake as a simple aquatic ecosystem, interpret how various functions of this ecosystem are carried out. Make a food chain that is functional in this ecosystem.