NEET Biology Biotechnology Principles and Processes MCQs Set 06

Answer: (a) Genus of the organism

Explanation:
1. In EcoRI, E stands for the genus Escherichia.
2. The next two letters come from the species name (co from coli).

Teacher's Note:
1. R is the strain and I is the order of isolation.

Answer: (c) Plasmid

Explanation:
1. Plasmids are small circular DNA molecules that replicate independently of the chromosome.
2. They are used as vectors.

Teacher's Note:
1. pBR322 is a plasmid vector.

Answer: (d) Origin of replication

Explanation:
1. The origin of replication (ori) is where replication begins.
2. It also controls the copy number of linked DNA.

Teacher's Note:
1. A foreign DNA needs ori to replicate in a host.

Answer: (a) Asexual reproduction

Explanation:
1. Asexual reproduction gives clones that retain the parent's genetic information.
2. Sexual reproduction mixes genes by recombination.

Teacher's Note:
1. Clones are genetically identical.

Answer: (c) It remains active during the high temperature of denaturation

Explanation:
1. Taq polymerase comes from Thermus aquaticus.
2. It remains active at the high temperatures used for denaturation of DNA.

Teacher's Note:
1. It is thermostable.

Answer: (a) Bioreactors

Explanation:
1. Bioreactors can process 100-1000 litres of culture.
2. The other names are not standard terms.

Teacher's Note:
1. They provide optimum conditions like temperature, pH and oxygen.

Answer: (c) DNA ligase

Explanation:
1. DNA ligase joins DNA fragments by forming phosphodiester bonds.
2. It is therefore the genetic glue.

Teacher's Note:
1. Restriction enzymes are the molecular scissors.

Answer: (a) Primers

Explanation:
1. Two sets of primers are used in PCR.
2. They anneal to the DNA template and start synthesis.

Teacher's Note:
1. Primers provide a free 3' OH end.

Answer: (c) Sea weeds

Explanation:
1. Agarose is a natural polymer extracted from sea weeds.
2. It forms the gel for sieving DNA fragments.

Teacher's Note:
1. DNA is negatively charged and moves to the anode.

Answer: (b) Cellulase

Explanation:
1. Plant cell wall is made of cellulose and is digested by cellulase.
2. Lysozyme is for bacteria and chitinase for fungi.

Teacher's Note:
1. Bacterial cells need lysozyme.

Answer: (a) Retroviruses

Explanation:
1. Retroviruses can transform normal animal cells into cancerous cells.
2. Disarmed retroviruses are used as vectors in animals.

Teacher's Note:
1. The analogy is why disarmed forms are used.

Answer: (c) Blue colonies

Explanation:
1. Non-recombinants have active beta-galactosidase.
2. It hydrolyses the chromogenic substrate to give blue colonies.

Teacher's Note:
1. Recombinants give white colonies.

Answer: (b) 42 degrees C

Explanation:
1. Cells are incubated with DNA on ice, then placed at 42 degrees C briefly, and then put back on ice.
2. This makes bacteria take up recombinant DNA.

Teacher's Note:
1. Divalent cations like calcium help the DNA uptake.

Answer: (a) Anode

Explanation:
1. DNA is negatively charged because of its phosphate groups.
2. It moves towards the positive electrode, the anode.

Teacher's Note:
1. Smaller fragments move farther.

Answer: (c) Introduction of unidentified DNA into the host

Explanation:
1. The identified DNA with a desired gene is introduced.
2. Introducing unidentified DNA is not a step in genetic modification.

Teacher's Note:
1. These steps are the basis of rDNA technology.

Answer: (c) Both simple stirring and sparged stirring types

Explanation:
1. Stirred-tank bioreactors are the most common.
2. They may be simple stirring or sparged types.

Teacher's Note:
1. Sparging bubbles sterile air.

Answer: (b) 5'-GAATTC-3' / 3'-CTTAAG-5'

Explanation:
1. EcoRI cuts between G and A in 5'-GAATTC-3'.
2. The complementary strand is 3'-CTTAAG-5', which reads the same in the 5' to 3' direction.

Teacher's Note:
1. AAGCTT is the site of HindIII.

Answer: (d) Restriction endonucleases

Explanation:
1. Two enzymes in E. coli restricted bacteriophage growth.
2. One was a restriction endonuclease which cut DNA and the other added a methyl group.

Teacher's Note:
1. They led to restriction enzyme technology.

Answer: (c) Ti plasmid of Agrobacterium tumefaciens

Explanation:
1. The Ti plasmid of Agrobacterium tumefaciens transfers T-DNA into plant cells.
2. It is disarmed and used as a cloning vector.

Teacher's Note:
1. Salmonella plasmid was used in the first rDNA experiment.

Answer: (c) European Federation of Biotechnology

Explanation:
1. The European Federation of Biotechnology (EFB) gave the definition.
2. It includes traditional processes and gene technology.

Teacher's Note:
1. It says biotechnology is the integration of natural science and organisms.

Answer: (d) 94 degrees C

Explanation:
1. Denaturation is at about 94 degrees C.
2. Annealing is at about 54 degrees C and extension at about 72 degrees C.

Teacher's Note:
1. Each cycle has three steps.

Answer: (a) The order in which the enzymes were isolated from that strain of bacteria

Explanation:
1. In EcoRI, the Roman number I shows it was the first enzyme isolated from the strain.
2. The R is the strain.

Teacher's Note:
1. HindII and HindIII are from the same bacterium.

Answer: (b) The ability to produce colour in the presence of a chromogenic substrate

Explanation:
1. Recombinants and non-recombinants are differentiated by colour production in a chromogenic substrate.
2. This replaced antibiotic selection.

Teacher's Note:
1. It is based on insertional inactivation.

Answer: (c) 1972

Explanation:
1. Cohen and Boyer constructed the first recombinant DNA in 1972.
2. They used a plasmid of Salmonella typhimurium.

Teacher's Note:
1. It marked the beginning of genetic engineering.