Biotechnology: Principles and Processes

During the process of isolation of DNA, chilled ethanol is added to :

1. Break open the cell to release DNA
2. Remove proteins such as histones
3. Facilitate action of restriction enzymes
4. Precipitate DNA

Biolistics (gene-gun) is suitable for

1. DNA finger printing
2. Constructing recombinant DNA by joining with vectors
3. Disarming pathogen vectors
4. Transformation of plant cells

In genetic engineering, the antibiotics are used

1. As sequences from where replication starts
2. As selectable markers
3. To keep the cultures free of infection
4. To select healthy vectors

Which one of the following represents a palindromic sequence in DNA ?

1. 5′-GAATTC-3′ 3′-CTTAAG-5′
2. 5′-GATACC-3′ 3′-CCTAAG-5′
3. 5′-CCAATG-3′ 3′-GAATCC-5′
4. 5′-CATTAG-3′ 3′-GATAAC-5′

The figure below shows three steps (A, B, C) of Polymerase Chain Reaction (PCR). Select the option giving correct identification together with what it represents ? [figure]

1. C - Extension in the presence of heat stable DNA polymerase
2. B - Denaturation at a temperature of about 98 separating the two DNA strands
3. A - Denaturation at a temperature of about 50
4. A - Annealing with two sets of primers

The figure below is the diagrammatic representation of the E. coli vector pBR322. Which one of the given options correctly identifies its certain component(s)? [figure]

1. ori - original restriction enzyme
2. ampR, tetR - antibiotic resistance genes
3. rop - reduced osmotic pressure
4. Hind III, EcoR I - selectable markers

Which one is a true statement regarding DNA polymerase used in PCR?

1. It is used to ligate introduced DNA in recipient cell
2. It remains active at high temperature
3. It serves as a selectable marker
4. It is isolated from a virus

For transformation, microparticles coated with DNA to be bombarded with gene gun are made up of

1. Gold or tungsten
2. Platinum or zinc
3. Silver or platinum
4. Silicon or platinum

Which one of the following techniques made it possible to genetically engineer living organisms?

1. Recombinant DNA techniques
2. X-ray diffraction
3. Heavier isotope labeling
4. Hybridization

Read the following four statements (A-D) with certain mistakes in two of them. Which are the two statements having mistakes?

1. Statements (B) and (C)
2. Statements (A) and (C)
3. Statements (A) and (B)
4. Statements (C) and (D)