This Page Score: 0/40
Assertion (A):
Retroviruses are modified and used as vectors to deliver desirable genes into animal cells.
Reason (R):
Retroviruses in animals have the natural ability to transform normal cells into cancerous cells, which provided the knowledge base for generating useful gene delivery tools.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The tumor inducing (Ti) plasmid of Agrobacterium tumifaciens is used in its natural, pathogenic form as a cloning vector for gene delivery into dicot plants.
Reason (R):
Agrobacterium tumifaciens is a pathogen that naturally delivers T-DNA to transform normal plant cells into a tumor.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
To isolate pure DNA from animal tissue, the cells must be treated with enzymes like cellulase and chitinase.
Reason (R):
Cell walls and membranes must be broken open to release DNA along with other macromolecules like RNA and proteins.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Purified DNA ultimately precipitates out of the solution after the addition of chilled ethanol.
Reason (R):
The precipitated DNA is collected by cutting the DNA bands out of the agarose gel and extracting them through a process called elution.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The technique of bioprocess engineering requires the maintenance of a sterile ambience in chemical engineering processes.
Reason (R):
Maintaining sterility ensures the growth of only the desired microbe or eukaryotic cell in large quantities for manufacturing biotechnological products like antibiotics and vaccines.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
The Polymerase Chain Reaction (PCR) synthesizes multiple copies of the DNA of interest in vitro.
Reason (R):
The reaction uses two sets of primers, which are small chemically synthesised oligonucleotides complementary to regions of the DNA template.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
A vector should be chosen based on its origin of replication to recover a desired number of copies of the target DNA.
Reason (R):
The origin of replication sequence is responsible for controlling the copy number of the linked DNA.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
During gel electrophoresis, DNA fragments move towards the cathode (negative electrode) because they are negatively charged molecules.
Reason (R):
The most commonly used matrix for separation is agarose, a natural polymer extracted from sea weeds, which provides a sieving effect.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Pure DNA fragments in an agarose gel can be seen easily in visible light after staining with ethidium bromide.
Reason (R):
The separated DNA fragments must be stained with ethidium bromide and exposed to UV radiation, where they appear as bright orange bands.
[Biotechnology-Principles-and-Processes] [class-xii ]
Assertion (A):
Downstream processing must be applied to all biotechnological products after the biosynthetic stage.
Reason (R):
This processing is mandatory as it includes separation, purification, formulation with preservatives, and strict quality control testing of the product before marketing.
[Biotechnology-Principles-and-Processes] [class-xii ]
This Page Score: 0/40