Subject

Life Sciences

Class

CNET Class 12

Pre Boards

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Sample Papers

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 Multiple Choice QuestionsMultiple Choice Questions

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1.

During an experiment, a student found increased activity of a protein, for which there were three possible explanations, viz, increased expression of the protein, increased phosphorylation, or increased interaction with other effector proteins. After conducting several experiments, the student concluded that increased activity was due to increased phosphorylation. Which one of the following experiments will NOT support/ provide the correct explanation drawn by the student?

  • Western blot analysis

  • Analysis of transcription rate

  • Mass spectroscopy

  • Phospho aminoacid analysis


2.

You have transiently expressed a new protein (for which no antibody is available) in a cell line to establish structure-function relationship. Which one of the following strategies is the most straight forward way to examine the expression profile of this new protein?

  • By metabolic labelling using 35S labelled amino acids.

  • Making a GFP fusion protein with this new protein.

  • Immunoprecipitating this protein with the help of another protein for which antibody is available.

  • Running SDS-PAGE and identify the protein


3.

Fluorescence recovery after photobleaching in live cells is used to determine

  • co-localization of proteins

  • distance between two organelles

  • diffusion of proteins

  • nucleic acid compactness


4.

A researcher is studying the subcellular localization of a particular protein 'X' in an animal cell. The researcher performs successive centrifugation at increasing rotor speed. The researcher starts spinning the cellular homogenate at 600g for 10 min, collects the pellet, spins the supernatant at 10,000 g for 20 min, collects the pellet, spins the supernatant at 100,000 gm for 1 hour, collects both the pellet and the final supernatant. On subjecting various pellets and the final supernatant to Western blotting with anti-protein-X antibody, the protein X is observed to be maximally expressed in the pellet after centrifugation at 10,000 g. Based on the above observation, what will be the most localization of protein X.

  • Nucleus

  • Ribosomes

  • Mitochondria

  • Microsomes


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5.

Which one of the following statements is correct?

  • Electrospray ionization mass spectrum of a compound can be obtained only if it has a net positive charge at pH 7.4.

  • Helical content of a tryptophan-containing peptide can be obtained by examining the fluorescence spectrum of tryptophan.

  • The occurrence of a beta-sheet in a protein can be inferred from its circular dichroism spectrum.

  • The chemical shift spread for a compound is more in its 1H NMR spectrum as compared to its 13C NMR spectrum.


6.

The following statements are related to plant tissue culture

A. Friable callus provides the inoculum to form cell-suspension cultures.

B. The process known as 'habituation' refers to the property of callus loosing the requirement of auxin and/or cytokinin during long term culture.

C. Cellulase and pectinase enzymes are usually used for generating protoplast cultures.

D. During somatic embryo development, torpedo stage embryo is formed before heart stage embryo.

Which one of the following combinations of above statements is correct?

  • A, B and C

  • A, B and D

  • A, C and D

  • B, C and D


7.

Glucose in the blood is detected by four different methods (a, b, c, and d). The sensitivity and range of detection of glucose by these four methods is shown below. Clinically relevant concentration of glucose in blood is between 80 - 250 mg/dL.

Which of the following method is most appropriate?

  • a

  • b

  • c

  • d


8.

A mixture of two proteins was subjected to following three chromatographic columns: a) Cation exchange, b) Size exclusion (Sephadex 100) and c) Reverse phase. Following elution profiles were obtained

Which of the following statements is correct?

  • A is larger and more hydrophobic than B.

  • B is more anionic and more hydrophobic than A.

  • A is more hydrophobic and smaller than B.

  • A is more cationic and smaller than B.


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9.

A student noted the following points regarding Agrobacterium tumefaciens:

A. A. tumefaciens is a gram-negative soli bacterium.

B. Opine catabolism genes are present in T-DNA region of Ti-plasmid.

C. Opines are synthesized by compensation of amino acids and α-ketoacids or amino acids and sugar.

D. A callus culture of crown gall tissue caused by A. tumefaciens in plants can be multiplied without adding phytohormone.

Which one of the combinations of above statements is correct?

  • A, B, and C

  • A, B, and D

  • B, C, and D

  • A, C, and D


10.

As cancer progresses, several genome rearrangements include translocation, deletion, duplications, etc,. occur. If these rearrangements are to be identified, which of the following techniques would be most suitable?

  • RAPD

  • Microarray

  • Multi-colour FISH

  • Flow cytometry


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