Bacteriophage does not repetitive sequences such as (i.e. 5386bp) and have all the coding sequence.Therefore, DNA fingerprint is not done for phages.

(i) Polymorphism is inherited from parents to children.So, it is useful for the identification(forensic application) and paternity testing. It arises due to mutations and also plays an important role in evolution and speciation.These  mutations in the evolution in the non-coding sequences have piled up with time and form the basis of DNA polymorphism.IT is basis of genetic of human genome as well as DNA fingerprinting.
(ii) Variable Number of Tandem Repeats(VNTRs) belong to a class of satellite DNA called as minisatellite.VNTR are used as probes in DNA fingerprinting..

(i) i-Regulatory gene, p - Promotor gene.
(ii) Inducer is lactose.
Functions
(a) Enters the cell and binds to the repressor and inactivates it.
(b) As a result, repressor cannot bind to the operator .This allows  RNA polymerase to have access to the promotor and transactions proceeds.

The core part of nucleosome comprises of 8 Histone molecules.DNA molecules is negatively charged whereas histone octomer is positively charged.Therefore, negatively charged DNA binds with the positively charged histone octomer

(a) Avery, MacCleod and McCarty gave the proof that "Transforming agent" is DNA
Avery, MacCleod and McCarty experiment:
1) Oswald Avery, colin MacCleod and McCarty in 1933-34 revealed the chemical nature of the transforming substance to be DNA
2) They purified DNA, RNA, Protein from heat-killed S-strain to see which of them could transform R-cells \(\rightarrow \)S-cells.
3) They also observed that protein digesting enzyme (protease) and RNA digesting enzyme (RNAase) have no effect on transformation whereas digestion of DNA with DNAase would not cause transformation
4) This finding established that transforming genetic material is DNA
Result of experiment

(b) Griffith's in vitro experiments demonstrated the occurrence of transformation in Pneumococcus. They provide no indication as to the molecular basis of the transformation phenomenon. Avery and MacCleod carried their experiments in vitro employing biochemical analysis to demonstrate that transformation was mediated by DNA
(c) Griffith showed that a transforming substance existed. Avery et.al. defined it as DNA

Living organisms are composed of various biomolecules and there are two main macromolecules, i.e., DNA and proteins which can have structural specificity as diverse as the basic requirement of genetic material
It was believed that proteins could be the ideal candidates for genetic material because:
(1) Proteins are made up of twenty amino acids thus the diversity can be generated on the basis of the number of residues of each amino acid in a given protein and sequence of amino acid would be enormous.
(2) They are macromolecules and universally present.

primary structure of nucleic acid and protein

Tandemness in repeats provides many copies of the sequence for DNA fingerprinting and variability in nitrogen base sequences presents in them. Being individual-specific, this proves to be useful in the process of DNA fingerprinting.

(i) While replicating, the entire DNA molecule to keep the whole molecule stabilised does not open in one go because it would be highly expense energetically. Actually un unwidinsg creates tension in the molecule as uncoiled parts.
Actually, unwinding creates tension in the molecule as uncoiled parts starts forming super coils due to the interaction of exposed nucleotides.
(ii) Replication fork: Instead helicase enzyme, acts on the double strand at or site (origin of replication and a small stretch is unzipped. Immediately. It is held and stabilised by single strand binding  protein.
Slowly with the help of enzymes, exposed strands are copied as a point of unwinding moves and ahead in both direction
It gives an appearence of Y-shaped structure which is called replication fork.
The two functions that the monorner units of NTPs play are:
1. They pair up with exposed nucleotides of the template strand and make phosphodiester linkages and release a pyrophosphate.
2. Hydrolysis of his pyrophosphate by enzyme pyrophosphate release energy that will facilitate making hydrogen bonds between free nucleotides and bases of the template strand

1) By using the heavy isotope of nitrogen.they could find out the semiconservative nature of DNA replication as the densities of DNA having in\( { 15 }_{ N }\) both the strands \( { 15 }_{ N }/{ 14 }_{ N }\) DNA and \( { 14 }_{ N }/{ 14 }_{ N }\) DNA were all different.
2) The hybrid DNA (\( { 15 }_{ N }/{ 14 }_{ N }\) DNA ) had a density intermediate between that of heavy DNA  (\({ 15 }_{ N }/{ 15 }_{ N }\) DNA) and that of light/normal DNA (\({ 14 }_{ N }/{ 14 }_{ N }\) DNA)