Which of the following statements are incorrect with respect to nucleotides ?
(A) Purines and pyrimidines are nitrogenous bases.
(B) Nucleotides and nucleosides are same.
(C) Phosphate group is linked to - OH of 5' C of a nucleoside through phosphoester linkage.
(D) In RNA, every nucleotide residue has an additional - OH group present at 3' position in the ribose.
(E) Thymine is an example of Pyrimidine.
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HIV primarily destroys which cells of the immune system?

Read the following paragraph and answer the given questions:
In order to link the alien DNA, the vector needs to have very few, preferably single, recognition sites for the commonly used restriction enzymes. Presence of more than one recognition site in the vector will generate several fragments, which will complicate the gene cloning. In order to link the alien DNA, the vector needs to have very few, preferably single, recognition sites for the commonly used restriction enzymes. Presence of more than one recognition sites within the vector will generate several fragments, which will complicate the gene cloning. The ligation of alien DNA is carried out at a restriction site present in one of the two antibiotic resistance genes. The recombinant plasmids will lose tetracycline resistance due to insertion of foreign DNA but can still be selected out from non-recombinant ones by plating the transformants on tetracycline containing medium.
The recombinants will grow in ampicillin containing medium but not on that containing tetracycline. But, non- recombinants will grow on the medium containing both the antibiotics. In this case, one antibiotic resistance gene helps in selecting the transformants, whereas the other antibiotic resistance gene gets 'inactivated due to insertion' of alien DNA, and helps in selection of recombinants. Origin of replication (ori) is a sequence from where replication starts and any piece of DNA when linked to this sequence can be made to replicate within the host cells. This sequence is also responsible for controlling the copy number of the linked DNA. So, if one wants to recover many copies of the target DNA it should be cloned in a vector whose origin support has high copy number.
Multiple recognition sites in vector generate several fragments, which will complicate the-

Which of the following biofertilisers are free living in the soil?
(A) Anabaena
(B) Azospirillum
(C) Rhizobium
(D) Azotobacter

Which of the following is NOT a sexually transmitted disease?

Match List-l with List-ll

List-l (Genetic disorder)	List-II (Cause)
(A) Thalassemia	(I) 45+XΟ
(B) Sickle-cell anemia	(II) Formation of abnormal hemoglobin
(C) Klinefelter's syndrome	(III) Substitution of glutamic acid by valine
(D) Turner's syndrome	(IV) 47, XXY

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Read the following paragraph and answer the given questions.
Repeated amplification is achieved by the use of a thermostable DNA polymerase (isolated from a bacterium, Thermusaquaticus}), which remain active during the high temperature induced denaturation of double stranded DNA. The separated DNA fragments can be visualised only after staining the DNA with a compound known as ethidium bromide followed by exposure to UV radiation. The separated bands of DNA are cut out from the agarose gel and extracted from the gel piece. The convention for naming these enzymes is the first letter of the name comes from the genus and the second two letters come from the species of the prokaryotic cell from which they were isolated, e.g., EcoRI comes from Escherichiacoli} RY 13. In EcoRI, the letter 'R' is derived from the name of strain. Roman numbers following the names indicate the order in which the enzymes were isolated from that strain of bacteria. Stanley Cohen and Herbert Boyer accomplished this in 1972 by isolating the antibiotic resistance gene by cutting out a piece of DNA from a plasmid which was responsible for conferring antibiotic resistance. Since the DNA is enclosed within the membranes, we have to break the cell open to release DNA, RNA, protein, polysaccharides etc. The RNA can be removed by treatment with ribonuclease whereas proteins can be removed by treatment with protease. Other molecules can be removed by appropriate treatments and purified DNA ultimately precipitates out after the addition of chilled ethanol.

In the isolation process of genetic material, the purified DNA can be precipitated out after the addition of:

Match List - I with List - II.

List - I	List - II
(A) Raoult's Law	(I) \(\pi=C R T\)
(B) Henry's Law	(II) \(P=x_1 p_1^0+x_2 p_2^0\)
(C) Elevation in Boiling point	(III) \(P=K_H x\)
(D) Osmotic Pressure	(IV) \(\Delta T_b=k_b m\)

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At one place on earth, the resultant magnetic field is 0.25 G and the angle of dip is 45°. The horizontal component of earth's magnetic field will be

Consider two independent events A and B such that P(A) = 0.3, P(B) = 0.6.
match List - I with List - II

List - I	List - II
(A) P(A and B)	(I) 0.28
(B) P(A and not B)	(II) 0.18
(C) P(A or B)	(III) 0.12
(D) P(neither A nor B)	(IV) 0.72

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Arrange the stages of HIV infection in humans sequentially.
(A) Introduction of viral DNA in the cell
(B) Production of multiple viruses
(C) Infection of human cell by virus
(D) Incorporation of viral DNA into host genome
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\(A\) runs \(3\) times as fast as \(B\) . If A gives \(B\) a start of \(30\) meters, how far must the goal on the race course be so that \(A\) and \(B\) reach it at the same time?

Identify the order of reaction if its rate constant is \(k = 2 \times 1 0 ^{- 2 } s ^{- 1 }\) :