In the insect gut, the Bt toxin protein is converted from an inactive protoxin to its active form due to the:
The Bt toxin protein exists as an inactive protoxin, but once ingested by an insect, it is converted into an active form due to the alkaline pH of the gut, which solubilizes the protein crystals.
Question 22 of 494
📘 CLASS XII
Which specific Bt toxin gene controls the corn borer?
The proteins encoded by the genes cryIAc and cryIIAb control the cotton bollworms, while the gene cryIAb controls the corn borer.
Question 23 of 494
📘 CLASS XII
RNA interference (RNAi) acts as a method of cellular defense in all eukaryotic organisms by causing the silencing of a specific mRNA due to a complementary:
RNA interference (RNAi) involves the silencing of a specific mRNA because a complementary double-stranded RNA (dsRNA) molecule binds to it, preventing its translation.
Question 24 of 494
📘 CLASS XII
In the transgenic host plant designed to resist the nematode Meloidegyne incognitia, how was the necessary double-stranded RNA (dsRNA) generated?
Nematode-specific genes were introduced via Agrobacterium vectors such that the introduction of DNA produced both sense and anti-sense RNA in the host cells. These complementary RNAs formed a dsRNA, initiating RNAi.
Question 25 of 494
📘 CLASS XII
A major advantage of recombinant therapeutics over similar products isolated from non-human sources is that they:
Recombinant therapeutics do not induce unwanted immunological responses, which is common in products isolated from non-human sources (like animal insulin). They are also free from the risk of infection.
Question 26 of 494
📘 CLASS XII
How many recombinant therapeutics approved for human use worldwide are currently marketed in India?
At present, about 30 recombinant therapeutics have been approved for human use worldwide. In India, 12 of these are presently being marketed.
Question 27 of 494
📘 CLASS XII
Mature insulin consists of two short polypeptide chains, Chain A and Chain B, linked together by:
Insulin consists of two short polypeptide chains: Chain A and Chain B, that are linked together by disulphide bridges.
Question 28 of 494
📘 CLASS XII
Insulin is synthesized in mammals as a pro-hormone. What is the extra stretch that needs to be removed for it to become a mature and functional hormone?
Insulin is synthesized as a pro-hormone, which contains an extra stretch called the C peptide. This C peptide is removed during maturation into functional insulin.
Question 29 of 494
📘 CLASS XII
What is the primary goal of Gene Therapy?
Gene therapy is a collection of methods allowing correction of a gene defect diagnosed in a child/embryo. It involves inserting genes into a person’s cells and tissues to treat a disease by delivering a normal gene to compensate for the non-functional one.
Question 30 of 494
📘 CLASS XII
If the ADA gene isolated from marrow cells is introduced into cells at early embryonic stages, the treatment for ADA deficiency could potentially be:
While current gene therapy for ADA requires periodic infusion of genetically engineered lymphocytes, if the gene is introduced into cells at early embryonic stages, it could be a permanent cure.
