With reference to recent developments regarding 'Recombinant Vector Vaccines', consider the following statements : 1. Genetic engineering is applied in the development of these vaccines. 2. Bacteria and viruses are used as vectors. Which of the statements given above is/are correct?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Correct answer
Explanation
The correct answer is C, Both 1 and 2. Recombinant vector vaccines are made by genetic engineering, and both viruses and bacteria serve as their vectors.
In a recombinant vector vaccine, scientists take a harmless or weakened carrier, the vector, and insert into it the gene for an antigen of the disease-causing germ. When the vector enters the body, it makes that antigen, and the immune system learns to recognise and fight the real pathogen without the person ever being exposed to it. Viral vectors such as adenoviruses are the most common; the Covishield vaccine used a chimpanzee adenovirus and Sputnik V used human adenoviruses to carry the coronavirus spike protein gene. Weakened bacteria such as Salmonella and the BCG strain have also been engineered as vectors.
A is wrong because statement 2 is also true. B is wrong because statement 1 is also true. D is wrong because both statements are correct.
Exam tip: viral vector vaccines: Covishield (chimpanzee adenovirus) and Sputnik V (human adenovirus).
Practice Questions
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- B.1 atmosphere
- C.1 bar
- D.1 poise
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- B.respectively transverse and longitudinal in air
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- D.both transverse in air
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- A.Charcoal
- B.Coke
- C.Fullerene
- D.Carbon black
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Read the full explanation →A planet has a mass M₁ and radius R₁. The value of acceleration due to gravity on its surface is g₁. There is another planet 2, whose mass and radius both are two times that of the first planet. Which one of the following is the acceleration due to gravity on the surface of planet 2?
- A.g₁
- B.2g₁
- C.g₁/2
- D.g₁/4
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Read the full explanation →Which one of the following is the major constituent of biogas ?
- A.Carbon dioxide
- B.Nitrous oxide
- C.Methane
- D.Oxygen
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