(i) Describe the various steps of Griffith's experiment that led to the conclusion of the 'transforming principle'.
(ii) How did the chemical nature of the 'transforming principle'get established?

Study the schematic representation of the genes involved in the lac operon given below and answer the question that follows.

i) Identify and name the regulatory gene in this operon .Explain its role in 'switching off' the operon.
(ii) Why is lac operon's regulation referred to as negative regulation?
(iii) Names the inducer molecule and the products of the genes 'z' and 'y' of the operon.Write the function of these gene products
(iii) Names the inducer molecule and the products of the genes 'z' and 'y' of the operon.Write the function of these gene products.

Differentiate between the following
(a) Repetitive DNA and Satellite DNA
(b) mRNA and tRNA
(c) Template strand and Coding strand

(i)  Explain the process of DNA replication with the help of a schematic diagram.
(ii) In which phase of the cell cycle does replication occur in eukaryotes? What would happen if cell division is not followed after DNA replication?

Raj was a known sportsman in his school.While returning home he found unknown miscreants beating a young fellow.He tried to drive them off but by that time the fellow died of injury.The police arrested Raj and he was put on trial.The judge being convinced by Raj's plea, ordered for DNA fingerprinting reports.
(i) What is the basis of DNA fingerprinting?
(ii) Explain the steps in DNA fingerprinting.
(iii) Write the applications of DNA fingerprinting.
(iv) Raj's fingerprints on the dead body were sufficient to convict him but the judge asked for authentic proof.What values can observed by the judge?