If a plasmid contains a selectable marker but lacks an *ori* sequence, what would be the result after transformation into the host?
The origin of replication is responsible for initiating replication; without it, the alien DNA cannot multiply itself.
Question 332 of 535
📘 CLASS XII
The DNA polymerase enzyme used in PCR is thermostable, which means it remains active during the high temperature needed for:
The thermostable DNA polymerase remains active during the high temperature induced denaturation of double stranded DNA.
Question 333 of 535
📘 CLASS XII
Which feature distinguishes a simple stirred-tank bioreactor from a shake flask?
Stirred tank bioreactors have agitator and oxygen delivery systems, which provide better aeration and mixing than shake flasks.
Question 334 of 535
📘 CLASS XII
The purpose of the enzyme *lysozyme* in the initial steps of RDT is to:
Lysozyme is used to treat bacterial cells to break the cell open and release DNA.
Question 335 of 535
📘 CLASS XII
Why are single recognition sites for restriction enzymes preferred in a cloning vector?
Presence of more than one recognition site within the vector will generate several fragments, which will complicate the gene cloning.
Question 336 of 535
📘 CLASS XII
If a non-recombinant plasmid is used in chromogenic selection, why do the colonies turn blue?
If the plasmid does not have an insert (non-recombinant), the gene for $\beta$-galactosidase is intact, and its enzyme breaks down the chromogenic substrate to produce blue colour.
Question 337 of 535
📘 CLASS XII
Which element is required in addition to an agitator system, oxygen delivery system, foam control system, and temperature control system in a bioreactor?
A bioreactor includes sampling ports so that small volumes of the culture can be withdrawn periodically.
Question 338 of 535
📘 CLASS XII
The use of "disarmed pathogen" vectors is a method specifically for introducing alien DNA into:
Disarmed pathogens (like modified Ti plasmid or retroviruses) are used to infect and transfer recombinant DNA into eukaryotic hosts (plant or animal cells).
Question 339 of 535
📘 CLASS XII
Before restriction enzyme digestion, the DNA must be in pure form, which means it must be free from other macromolecules. Which enzyme is used to remove histone proteins from the DNA preparation?
Proteins (including histones) can be removed by treatment with protease.
Question 340 of 535
📘 CLASS XII
Why is the maintenance of sterile ambience (bioprocess engineering) critical for the manufacture of biotechnological products?
Bioprocess engineering is the maintenance of sterile (microbial contamination-free) ambience to enable growth of only the desired microbe.
