Tag: genetic technology
Questions Related to genetic technology
The correct sequence of making a cell competent is
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Treatment with divalent cations incubation of cells with recombinant DNA on ice heat shock ($42^0$C) placing on ice
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Heat shock ($42^0$C) incubation of cells with recombinant DNA on ice treatment with divalent cations placing on ice
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Treatment with divalent cations placing on ice incubation of cells with recombinant DNA on ice heat shock ($42^0$C)
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Incubation of cells with recombinant DNA on ice heat shock ($42^0$C) treatment with divalent cations placing on ice
In order to force a bacteria to take up the plasmid , the bacterial cells must to be made competent. This is done by treating them with a specific concentration of divalent cations such as calcium which increases the efficiency with which the DNA molecule enters into the bacteria through pores in its cell wall. Recombinant DNA then forced into such cells by incubating the cells with recombinant DNA on ice followed by placing them immediately at heat shock and then again into ice. This enables the bacteria to take up the recombinant DNA.
rDNA is
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Genomic RNA of virus
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Genomic RNA that produces DNA through reverse transcription
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DNA found in ribosome
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DNA segment speciaiised to form rRNA
Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. Ribosomes are assemblies of proteins and rRNA molecules that translate mRNA molecules to produce proteins. In the nucleus, the rDNA region of the chromosome is visualized as a nucleolus which forms expanded chromosomal loops with rDNA.
Chimeric DNA is
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Gene clone
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Recombinant - DNA
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Transposon
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Vector shuttle
- Recombinant DNA molecules are sometimes called chimeric DNA, because they can be made of material from two different species, like the mythical chimera.
- A chimera is essentially a single organism that is made up of cells from two or more individuals—that is, it contains two sets of DNA, with the code to make two separate organisms.
- R-DNA technology uses palindromic sequences and leads to the production of sticky and blunt ends.
Two bacteria found to be very useful in genetic engineering experiment are
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Nitrosomonas and Klebsiella
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Escherichia and Agrobacterium
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Nitrobacter and Azotobacter
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Rhizobium and Diplococcus
Till today, the most important in genetic engineering of plants has been the Ti plasmid of soil bacterium, Agrobacterium tumefaciens. E.Coli has been extensively used as "work horse" for genetic engineering e.g., production of humulin, somatotropin. E. coli is one of the most thoroughly studied of all living things. It is a favorite organism for genetic engineering as cultures of it can be made to produce unlimited quantities of the product of an introduced gene. Several important drugs (insulin, for example) are now manufactured in E. coli. Thus, option B is correct. Nitrosomonas, Klebsiella, Nitrobacter, Azotobacter, Rhizobium and Diplococcus are not used in genetic engineering.
Which of the following most used in genetic engineering?
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E.coil and Agrobacterium
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Mycobacteria and Salmonella
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Aspergillus
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Penicillium
Genetic engineering is a branch of science that uses various biotechnological techniques to manipulate an organism's genome to create species with desired traits. However, the process involves isolation, transfer and insertion of the new genetic material into host genomes and storage of genomes in organisms and selective markers for an indefinite period. Experiments have shown that certain bacteria has the ability to naturally take in and express foreign DNA. It has been found that of these, E.coli has the ability to transfer DNA laterally to and from other species while Agrobacterium can transfer genes to plants and fungi by causing crown gall disease.
Two bacteria most useful in genetic engineering are
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Rhizobium and Azotobacter
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Escherichia and Agrobacterium
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Rhizobium and Diplococcus
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Nitrosomonas and Klebsiella
Competent host in recombinant DNA technology is __________________.
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Any human cancer cell
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The cell ready to update align DNA
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A host cell without cell wall
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Agrobacterium cell
Option 'D' is correct.
Which of the following is mostly used in genetic engineering experiments?
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Bacillus subtilis
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Rhizobium
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Staphylococcus
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Escherichia coli
Genetic engineering is a branch of science which uses a set of biotechnology techniques and knowledge of cytology and genetics to bring modifications to an organism's genome. For such research, scientists need to store and modify the genes and genetic information from wide range of organisms into organisms that can be easy to transform. Bacteria more commonly Escherichia coli is used to transform and create the genetically modified bacteria as this can be transformed and stored easily for indefinite periods at -80 C and replicate the modified DNA in short time period.
The uptake of naked DNA by bacteria is called
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Conjugation
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Transformation
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Transfection
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Transduction
R-II strain of $T 4$ bacteriophage cannot lyse Escherichia coli. Two of its types, R-$II^x$ and R-$II^y$ were allowed to invade the bacterium which lysed because of _________________.
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Transformation into wild type
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Presence of similar cistrons
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Presence of different cistrons
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Absence of mutation