Biotechnology: Principles and Processes

Restriction endonuclease -

1. Cuts the DNA molecule at specific sites
2. Synthesizes DNA
3. Restricts the synthesis of DNA inside the nucleus
4. Cuts the DNA molecule randomly

Two microbes found to be very useful in genetic engineering are-

1. Diplococcus sp. and Pseudomonas sp.
2. Vibrio cholerae and a tailed bacteriophage
3. Crown gall bacterium and Caenorhabditis elegans
4. Escherichia coli and Agrobacterium tumefaciens

Which one of the following hydrolyses internal phosphodiester bonds in a polynucleotide chain?

1. Protease
2. Endonuclease
3. Lipase
4. Exonuclease

The most thoroughly studied of the known bacteria-plant interactions is the :-

1. Nodulation of Sesbania stems by nitrogen fixing bacteria
2. Cyanobacterial symbiosis with some aquatic ferns
3. Plant growth stimulation by phosphate-solubilising bacteria
4. Gall formation on certain angiosperms by Agrobacterium

Restriction endonucleases :-

1. Are used for in vitro DNA synthesis
2. Are present in mammalian cells for degradation of DNA when the cell dies
3. Are synthesized by bacteria as part of their defense mechanism
4. Are used in genetic engineering for ligating two DNA molecules

In transgenics expression of transgene in target tissue is determined by :-

1. Enhancer
2. Promoter
3. Reporter
4. Transgene

The Ti plasmid is often used for making transgenic plants. This plasmid is found in

1. Agrobacterium
2. Rhizobium of the roots of leguminous plants
3. Azotobacter
4. Yeast as a 2 plasmid

Which one of the following bacteria has found extensive use in genetic engineering work in plants ?

1. Xanthomonas citri
2. Agrobacterium tumefaciens
3. Bacillus coagulans
4. Clostridium septicum

Which of the following enzymes are used to join bits of DNA ?

1. Endonuclease
2. DNA polymerase
3. Ligase
4. Primase

Manipulation of DNA in genetic engineering became possible due to the discovery of : -

1. Transcriptase
2. DNA ligase
3. Primase
4. Restriction endonuclease