In molecular diagnosis utilizing a probe and autoradiography, what is the probe typically tagged with?
A single stranded DNA or RNA, tagged with a radioactive molecule (probe) is allowed to hybridise to its complementary DNA in a clone of cells.
Question 52 of 494
📘 CLASS XII
If a clone contains a mutated gene during molecular diagnosis using a radioactive probe and autoradiography, what is the resulting observation?
If the gene is mutated, the radioactive probe will not have complementarity, and consequently, the clone having the mutated gene will not appear on the photographic film after autoradiography.
Question 53 of 494
📘 CLASS XII
What type of vector was used in the first clinical gene therapy for ADA deficiency to introduce the functional ADA cDNA into the lymphocytes?
As a first step towards gene therapy for ADA deficiency, a functional ADA cDNA (using a retroviral vector) is introduced into lymphocytes grown outside the body.
Question 54 of 494
📘 CLASS XII
Bone marrow transplantation and enzyme replacement therapy are listed as treatments for ADA deficiency, but both approaches suffer from the drawback that they are:
Bone marrow transplantation and enzyme replacement therapy, while used to treat ADA deficiency, are problematic because they are not completely curative.
Question 55 of 494
📘 CLASS XII
Recombinant therapeutics are considered superior to similar products isolated from non-human sources because they are free from the risk of infection and do not induce:
The recombinant therapeutics do not induce unwanted immunological responses as is common in case of similar products isolated from non-human sources, and are also free from the risk of infection.
Question 56 of 494
📘 CLASS XII
What is the fundamental principle behind the diagnostic technique ELISA (Enzyme Linked Immuno-sorbent Assay)?
ELISA is based on the principle of antigen-antibody interaction. It detects infection by identifying the presence of antigens (proteins, glycoproteins) or by detecting antibodies synthesized against the pathogen.
Question 57 of 494
📘 CLASS XII
Which type of molecule, when tagged with a radioactive molecule (probe), is used in molecular diagnosis followed by detection using autoradiography?
A single stranded DNA or RNA, tagged with a radioactive molecule (probe) is allowed to hybridise to its complementary DNA in a clone of cells.
Question 58 of 494
📘 CLASS XII
In the context of Bt toxin, what is the role of the alkaline pH in the insect gut?
The Bt toxin protein exists as an inactive protoxin. Once ingested, the alkaline pH of the gut solubilizes the crystals, converting the protoxin into the active form of the toxin.
Question 59 of 494
📘 CLASS XII
After activation, where does the Bt toxin bind within the insect body to initiate cell death?
The activated Bt toxin binds to the surface of midgut epithelial cells, creating pores that cause cell swelling and lysis, leading to the death of the insect.
Question 60 of 494
📘 CLASS XII
Besides Bt cotton, which of the following is listed as an example of a crop plant into which Bt toxin genes have been incorporated?
Examples of crop plants where Bt toxin genes have been incorporated include Bt cotton, Bt corn, rice, tomato, potato and soyabean.
