Which of the following biofertilisers are free living in the soil?
(A) Anabaena
(B) Azospirillum
(C) Rhizobium
(D) Azotobacter
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Which one of the following is an example of co-evolution?

Match List I with List II.

LIST I	LIST II
A. Agarose	I. Polymerase chain reaction
B. Thermostable DNA polymerase	II. Electrophoresis
C. Micro injection	III. Ampicillin resistance gene
D. Selectable marker	IV. Introduction of alien DNA in animal cell

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Read the given paragraph carefully and answer the following questions:
Since the DNA is enclosed within the membranes, we have to break the cell open to release DNA along with other macromolecules such as RNA, proteins, polysaccharides and also lipids. This can be achieved by treating the bacterial cells/plant or animal tissue with enzymes such as lysozyme (bacteria), cellulase (plant cells), chitinase (fungus). There are some basic steps in genetically modifying an organism (i) identification of DNA with desirable genes; (ii) introduction of the identified DNA into the host; (iii) maintenance of introduced DNA in the host and transfer of the DNA to its progeny. Agrobacterium tumifaciens, a pathogen of several dicot plants is able to deliver a piece of DNA known as 'T-DNA' to transform normal plant cells into a tumor and direct these tumor cells to produce the chemicals required by the pathogen. Other molecules can be removed by appropriate treatments and purified DNA ultimately precipitates out after the addition of chilled ethanol. Selection of recombinants due to inactivation of antibiotics is a cumbersome procedure because it requires simultaneous plating on two plates having different antibiotics. Therefore, alternative selectable markers have been developed which differentiate recombinants from non-recombinants on the basis of their ability to produce colour in the presence of a chromogenic substrate. In this, a recombinant DNA is inserted within the coding sequence of an enzyme, ß'-galactosidase. This results into inactivation of the gene for synthesis of this enzyme, which is referred to as insertional inactivation.
Agrobacterium tumefaciens, a pathogen of several dicot plants, is able to deliver a piece of DNA known as:

Which one of the following statements is incorrect about ecological pyramids?

The first human-like being the hominid was called as -

Which of the following are autosomal recessive trait/ disorder?
(A) Thalassemia
(B) Haemophilia
(C) Sickle cell anaemia
(D) Phenylketonuria
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Which of the following is TRUE for gel electrophoresis ?
(A) It is used to separate DNA fragments.
(B) Separation of DNA occurs on the basis of the fragment size.
(C) Separation of DNA fragments occurs on the basis of charge.
(D) Separated DNA fragments can be visualised without staining.
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Select the colligative property which is used in the calculation of molar mass of biomolecules.

The stain commonly used to visualise DNA fragments separated by gel electrophoresis is:

An external voltage is applied across a diode such that the n-side is positive and the p-side is negative. As a result,
(A) the barrier height decreases
(B) the barrier height increases
(C) the depletion region widens
(D) the depletion region width decreases
(E) no change in barrier height
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A current of \(1.0\) mA is flowing through a potentiometer wire of length 4 m and of resistance \( 40 \, \Omega \). The potential gradient of the potentiometer wire will be :

Activation energy (\(E_a\)) and rate constants (\(K_1\) and \(K_2\)) at two different temperature \(T_1\) and \(T_2\) respectively for a chemical reaction are related as :