During the purification process for recombinant DNA technology, addition of chilled ethanol precipitates out:

NEET-2021 [Biotechnology-Principles-and-Processes] [class-xii ]

• RNA
• DNA
• Histones
• Polysaccharides
Correct Option: B  [ DNA ]

Remark:

DNA strands on a gel stained with ethidium bromide when viewed under UV radiation, appear as:

NEET-2021 [Biotechnology-Principles-and-Processes] [class-xii ]

• Yellow bands
• Bright orange bands
• Dark red bands
• Bright blue bands
Correct Option: B  [ Bright orange bands ]

Remark:

Plasmid pBR322 has PstI restriction enzyme site within gene amp^R that confers ampicillin resistance. If this enzyme is used for inserting a gene for β-galactoside production and the recombinant plasmid is inserted in an E.coli strain

NEET-2021 [Biotechnology-Principles-and-Processes] [class-xii ]

• it will not be able to confer ampicillin resistance to the host cell.
• the transformed cells will have the ability to resist ampicillin as well as produce β-galactoside.
• it will lead to lysis of host cell.
• it will be able to produce a novel protein with dual ability.
Correct Option: A  [ it will not be able to confer ampicillin resistance to the host cell. ]

Remark:

During the process of gene amplification using PCR, if very high temperature is not maintained in the beginning, then which of the following steps of PCR will be affected first?

NEET-2021 [Biotechnology-Principles-and-Processes] [class-xii ]

• Annealing
• Extension
• Denaturation
• Ligation
Correct Option: C  [ Denaturation ]

Remark:

A specific recognition sequence identified by endonucleases to make cuts at specific positions within the DNA is:

NEET-2021 [Biotechnology-Principles-and-Processes] [class-xii ]

• Degenerate primer sequence
• Okazaki sequences
• Palindromic Nucleotide sequences
• Poly(A) tail sequences
Correct Option: C  [ Palindromic Nucleotide sequences ]

Remark:

Match the following techniques or instruments with their usage:

NEET-(Oct)2020 [Biotechnology-Principles-and-Processes] [class-xii ]

• (A)-(III), (b)-(II), (c)-(IV), (d)-(I)
• (A)-(II), (b)-(I), (c)-(IV), (d)-(III)
• (A)-(IV), (b)-(III), (c)-(II), (d)-(I)
• (A)-(II), (b)-(I), (c)-(III), (d)-(IV)
Correct Option: B  [ (A)-(II), (b)-(I), (c)-(IV), (d)-(III) ]

Remark:

First discovered restriction endonuclease that always cuts DNA molecule at a particular point by recognising a specific sequence of six base pairs is:

NEET-(Oct)2020 [Biotechnology-Principles-and-Processes] [class-xii ]

• EcoR1
• Adenosine deaminase
• Thermostable DNA polymerase
• Hind II
Correct Option: D  [ Hind II ]

Remark:

Select the correct statement from the following:

NEET-(Oct)2020 [Biotechnology-Principles-and-Processes] [class-xii ]

• Gel electrophoresis is used for amplification of a DNA segment.
• The polymerase enzyme joins the gene of interest and the vector DNA.
• Restriction enzyme digestions are performed by incubating purified DNA molecules with the restriction enzymes of optimum conditions.
• PCR is used for isolation and separation of gene of interest.
Correct Option: C  [ Restriction enzyme digestions are performed by incubating purified DNA molecules with the restriction enzymes of optimum conditions. ]

Remark:

In a mixture, DNA fragments are separated by:

NEET-(Oct)2020 [Biotechnology-Principles-and-Processes] [class-xii ]

• Bioprocess engineering
• Restriction digestion
• Electrophoresis
• Polymerase chain reaction
Correct Option: C  [ Electrophoresis ]

Remark:

In Recombinant DNA technology antibiotics are used:

NEET-(Oct)2020 [Biotechnology-Principles-and-Processes] [class-xii ]

• to keep medium bacteria-free
• to detect alien DNA
• to impart disease-resistance to the host plant
• as selectable markers
Correct Option: D  [ as selectable markers ]

Remark: