CSIR NET Life Science Previous Year Questions on applied biology Archives - Page 12 of 19 - CSIR NET LIFE SCIENCE COACHING | NTA NET LIFE SCIENCE

50. An experiment was performed to introduce a transgenic trait in a crop plant by Agrobacterium - mediated transformation using a transgene construct in which the transgene was expressed using the CaMV 355 promoter. It was observed that expression levels of the transgenic protein were very low in all transgenic plants while transgene mRNA levels were high and variable among different plants. Further, different transgenic lines contained different numbers of the T- DNA insert. The following statements were made to explain the above observation: (A) Variations in the number of T-DNA inserts in different transgenic plants is due to more number of host cells getting infected with the T- DNA (A) Low expression levels of the transgenic protein in all transgenic plants could be due to codon usage variations between the host plant and the heterologous source of the transgene (B) The coding sequence of the transgene contained sequences that destabilized the transgene mRNA (C) Variation in copy number of T-DNA in different transgenic plants is due to variation in the promoter used to express the transgene. Which one of the following options represents all correct statements? (1) A only (2) B and C (3) A and D (4) B only

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Why can a CaMV 35S-driven transgene show high mRNA but low protein?

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November 28, 2025
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An experiment was performed to introduce a transgenic trait in a crop plant by Agrobacterium – mediated transformation using a transgene construct in which the transgene was expressed using the […]

49. Given below is a figure representing expression levels of transgenic protein in ten independent transgenic plants generated using the same transformation vector by Agrobacterium-mediated transformation. Given below are a few statements to explain the above data: A. Plant nos. 4, 9 and 10 that show high expression levels of the transgene would necessarily contain multiple copies of the transgene. B. Plant nos. 2 and 7 contain mutations in the coding sequence of the transgene in the construct. C. The transgenic plants may contain varying number of transgene copies inserted at different locations in the host genome. D. The host genome has no role in influencing expression levels of the transgene. E. The stability of the transgenic mRNA and its translatability would not be different among the independent transgenic plants. Which one of the following options represents all correct statements? (1) A and D only (2) B and C only (3) C and E only (4) A, D and E only

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Why do independent transgenic events show different expression levels?

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November 28, 2025
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Given below is a figure representing expression levels of transgenic protein in ten independent transgenic plants generated using the same transformation vector by Agrobacterium-mediated transformation. Given below are a few […]

48. Agrobacterium mediated transformation was used to generate transgenic plants using a construct with a selection marker gene "X" and a passenger gene "Y". Expression levels of "Y" protein in eight independent transgenic plants are given below The following could represent probable reasons for the observed variability in transgene expression levels (A) Position effects on passenger gene (B) Transgene silencing of the marker gene (C) Variation in copy number of passenger gene (D) mRNA instability of marker gene Which one of the following combinations of above statements is correct? (1) A and C (2) C and D (3) B and D (4) A and B

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Why do independent transgenic plants show variable transgene expression?

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November 28, 2025
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Agrobacterium mediated transformation was used to generate transgenic plants using a construct with a selection marker gene “X” and a passenger gene “Y”. Expression levels of “Y” protein in eight […]

47. For the generation of transgenic plant in crop improvement, one important regulatory gene 'X' was overexpressed in a crop plant. Out of 30 transgenic rice plants generated, 22 showed high levels of gene 'X' expression. However, rest 8 lines displayed low level of expression. One explanation of such observation may be: (1) Suppression effect of the transgene (2) Knock down effect of gene X (3) Gene silencing effect (4) Co-suppression effect of transgene

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Why some overexpression lines show low expression of gene X in transgenic rice

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November 28, 2025
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For the generation of transgenic plant in crop improvement, one important regulatory gene ‘X’ was overexpressed in a crop plant. Out of 30 transgenic rice plants generated, 22 showed high […]

46. Which of the following genes was engineered in the "Flavr Savr" transgenic tomato variety? (1) 1-Amino cyclopropane-1-carboxylic acid synthase. (2) 1-Amino cyclopropane-1-carboxylic acid oxidase. (3) Expansin (4) Polygalacturonase.

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Which gene was engineered in the Flavr Savr tomato?

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November 28, 2025
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Which of the following genes was engineered in the “Flavr Savr” transgenic tomato variety? (1) 1-Amino cyclopropane-1-carboxylic acid synthase. (2) 1-Amino cyclopropane-1-carboxylic acid oxidase. (3) Expansin (4) Polygalacturonase. The correct […]

45. Which of the following transgenic crops have been approved for commercial cultivation in India? (1) Cotton (2) Brinjal (3) Cotton and Brinjal (4) Cotton, Brassica, Brinjal

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Approved transgenic crop for commercial cultivation in India

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November 28, 2025
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Which of the following transgenic crops have been approved for commercial cultivation in India? (1) Cotton (2) Brinjal (3) Cotton and Brinjal (4) Cotton, Brassica, Brinjal The correct answer is […]

44. Neomycin phospho-transferase gene, frequently used as a selection marker during plant transformation, inactivates which one of the following antibiotics? (1) Hygromycin (2) Ampicillin (3) Streptomycin (4) Kanamycin 44. Neomycin phospho-transferase gene, frequently used as a selection marker during plant transformation, inactivates which one of the following antibiotics? (1) Hygromycin (2) Ampicillin (3) Streptomycin (4) Kanamycin

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Neomycin phosphotransferase (NPT II) as a selectable marker in plant transformation

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November 28, 2025
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Neomycin phospho-transferase gene, frequently used as a selection marker during plant transformation, inactivates which one of the following antibiotics? (1) Hygromycin (2) […]

43. The following genes have been genetically engineered to develop herbicide resistance in plants: A. Resistance to glyphosate using the 5-enolpyruyl shikimate-3-phosphate synthase gene B. Bialaphos resistance using the bar gene C. Sulfonyl urea resistance using the acetolactate synthase D. Atrazine resistance using the glutathione S- transferase gene. In which of the above two cases the mechanism is based on abolition of herbicide binding to the enzyme? (1) A and D (2) B and C (3) C and D (4) A and C

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Which herbicide-resistance genes work by preventing herbicide binding to the target enzyme?

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November 28, 2025
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The following genes have been genetically engineered to develop herbicide resistance in plants: A. Resistance to glyphosate using the 5-enolpyruyl shikimate-3-phosphate synthase gene B. Bialaphos resistance using the bar gene […]

42. Which genes have been introduced in Bollgard II cotton to get resistance against cotton bollworm, tobacco bollworm and pink bollworm? (1) cry 1Ab + cry 1Ac (2) cry 1Ac + cry 2 Ab (3) cry 1Ab + cry 2 Ab (4) cry9 C cry 1Ab

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Which Bt genes are used in Bollgard II cotton?

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November 28, 2025
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Which genes have been introduced in Bollgard II cotton to get resistance against cotton bollworm, tobacco bollworm and pink bollworm? (1) cry 1Ab + cry 1Ac […]

41. Which of the following features is NOT shown by glyphosate, a broad spectrum herbicide? (1) Little residual soil activity (2) Ready translocation in phloem (3) Inhibition of a chloroplast enzyme catalyzing the synthesis of aromatic amino acids (4) Inhibition of early steps in the biosynthesis of branched chain amino acids

CSIR NET Life Science Previous Year Questions and Solution on applied biology

Key features and mode of action of glyphosate herbicide

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November 28, 2025
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Which of the following features is NOT shown by glyphosate, a broad spectrum herbicide? (1) Little residual soil activity (2) Ready translocation in phloem (3) Inhibition of a chloroplast enzyme […]

Tag: CSIR NET Life Science Previous Year Questions on applied biology

Why can a CaMV 35S-driven transgene show high mRNA but low protein?

Why do independent transgenic events show different expression levels?

Why do independent transgenic plants show variable transgene expression?

Why some overexpression lines show low expression of gene X in transgenic rice

Which gene was engineered in the Flavr Savr tomato?

Approved transgenic crop for commercial cultivation in India

Neomycin phosphotransferase (NPT II) as a selectable marker in plant transformation

Which herbicide-resistance genes work by preventing herbicide binding to the target enzyme?

Which Bt genes are used in Bollgard II cotton?

Key features and mode of action of glyphosate herbicide

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