List of top Questions asked in CBSE CLASS XII

Give the names of any three genes that are used as selectable markers in recombinant DNA technology. Also mention the trait/protein they specify.
What are zymogens? How is chymotrypsinogen different from chymotrypsin?
Discuss any three ways that can be employed to measure microbial cell growth.
A researcher performed protein fingerprinting on hemoglobin from both normal and sickled red blood cells. Complete the flow-chart of the process by filling A, B, and C.
A researcher performed protein fingerprinting
 
Explain the steps involved in PCR amplification method.
Write the therapeutic use and the animal cell line employed in obtaining any three of the following protein pharmaceuticals:
Compare the techniques of FISH with Microarray in terms of principle and applications.
Give any two drawbacks of animal cell culture in vitro.}
Write about any two strategies available to enhance the production of secondary metabolites in plant genetic engineering.
Name the technique that helps to study the entire protein profile from a given cell type. Briefly explain the principle of this method.
What are the advantages offered by creating a mouse model with gene knockout?
Illustrate steps to show the construction of a recombinant DNA molecule.
Assertion (A): During plant tissue culture, the explants are treated with sodium hypochlorite.
Reason (R): Sodium hypochlorite helps in acclimatization of the regenerated plants.
Assertion (A): The regulation of pH is essential for survival of mammalian cells.
Reason (R): Animal cell cultures mostly make use of Bicarbonate – carbon dioxide buffering system to maintain pH.
Assertion (A): The exact chemical composition of complex microbial growth media is known.
Reason (R): Complex nutrient media is used when specific growth requirement of a microorganism is unknown.
Assertion (A): Some experts believe that there must be more than 30,000 genes in human genome.
Reason (R): Unreliability of in silico gene prediction is responsible for reporting lesser number of genes in human genome.
________________________ cultures can be maintained for a prolonged period of time by repeated sub-culturing.
An improved strain of Penicillium, capable of producing higher concentration of antibiotic penicillin is:
Embryonic stem cells derived from the blastocyst stage of the embryo are ________________________ in nature.
A protein ion with a molecular weight of 10,000 Daltons carried a charge of 5+ and was subjected to mass spectrometric analysis. Calculate its mass to charge ratio.
When a transgene from a Genetically Modified crop escapes through pollen to a related plant species, it is known as:
An example of secondary metabolites produced by microbial cells include:
Identify the vector that infects E. coli cells containing F-plasmid and that has a single-stranded circular genome:}
The peptide hormones and growth factors to promote healthy growth of animal cells in vitro are often derived from:}
Artificial seeds are produced by encapsulating the somatic embryos at the ______________ stage in a protective coating.