Write the specific point in the palindrome and the bond that is cut by EcoRI.

Study the schematic representation of the genes involved in the lac operon given below and answer the questions that follow:

(a) Identify and name the regulatory gene in this operon. Explain its role in ‘switching off’ the operon.

(b) Why is the lac operon’s regulation referred to as negative

regulation?

(c) Name the inducer molecule and the products of the genes ‘z’ and ‘y’ of the operon. Write the functions of these gene products.

OR

(a) How does the Hardy-Wienberg equation explain genetic equilibrium?

(b) Describe how this equilibrium is disturbed that may lead to founder effect.

a) Study the flow chart given below and complete the equation that follows by identifying 1, 2, 3 and 4.

(b) Mention the different ways by which the population density of different species can be measured.

OR

(a) ‘The pyramid of energy is always upright.’ Explain.

(b) Explain with the help of labelled diagrams, the difference between an upright pyramid of biomass and an inverted pyramid of biomass.

Write the scientific name of the source from where cocaine is obtained. How does its use affect the human body?

How is an alien species invasion considered as one of the causes of biodiversity loss? Support your answer with the help of an example.