Question

15.
Read the following and answer any four questions from 15(i) to 15(v) given below:

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.
Similarly, retroviruses in animals have the ability to transform normal cells into cancerous cells. A better understanding of the art of delivering genes by pathogens in their eukaryotic hosts has generated knowledge to transform these tools of pathogens into useful vectors for delivering genes of interest to humans. The tumor inducing (Ti) plasmid of Agrobacterium tumifaciens has now been modified into a cloning vector which is no more pathogenic to the plants but is still able to use the mechanisms to deliver genes of our interest into a variety of plants. Similarly, retroviruses have also been disarmed and are now used to deliver desirable genes into animal cells. So, once a gene or a DNA fragment has
been ligated into a suitable vector it is transferred into a bacterial, plant or animal host (where it multiplies).






4

i.
Ti means
T-DNA producing enzymes
Tumefaciens inducing genes
Tumor inducing plasmid
Ticket intaking plasmid


ii.

Agrobacterium tumifaciens is a
Bacteria
BaculoVirus
Yeast
Protozoa




iii.
Retroviruses are
Present in ancient era
Reverse type viruses
No-infectious
Containing RNA as a genetic material


iv.
Tumor cells are
Very dangerous
Highly cancerous
produce the chemicals required by the pathogen
Present in all plants


v.
Assertion: Very small animals are rarely found in polar regions
Reason: Relative to their volume, small animals have large surface area. They tend to lose energy very fast when in cold outside.
Both assertion and reason are true, and the reason is the correct explanation of the assertion.
Both assertion and reason are true, but the reason is not the correct explanation of the assertion.
Assertion is true but reason is false.
Both assertion and reason are false

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Answer 1

Answer:

Lamba h Bhai

nhi aa rhi h smjh

Answer 2

Answer:

Itna bada question......I don't know about this question.Pakka kisine bhi iska answer nhi diya hoga