Recombinant DNA Technology: A Comprehensive Guide to Gene Cloning and Genetic Engineering

Question 1

In recombinant DNA technology, which enzyme is used to cut DNA at specific nucleotide sequences?

Accepted Answer

Restriction endonuclease

Answer

DNA polymerase

Answer

Reverse transcriptase

Answer

Ligase

Question 2

Which enzyme is primarily used to precisely cut DNA at specific sequences during Recombinant DNA Technology?

Accepted Answer

Restriction enzyme

Answer

Ligase

Answer

Polymerase

Answer

Helicase

Question 3

In the context of Recombinant DNA Technology, what is the primary purpose of a plasmid, a small circular DNA molecule commonly used in cloning?

Accepted Answer

To carry and amplify the foreign gene of interest

Answer

To transcribe the foreign gene into RNA

Answer

To translate the foreign gene into protein

Answer

To regulate the expression of the foreign gene

Question 4

Which step is not part of the polymerase chain reaction (PCR) process, a fundamental technique in Recombinant DNA Technology?

Accepted Answer

Ligation

Answer

Denaturation

Answer

Annealing

Answer

Extension

Question 5

When working with DNA cloning, a genetic marker plays a crucial role. What is its primary purpose?

Accepted Answer

To identify the recombinant cells containing the foreign gene

Answer

To amplify the cloned gene

Answer

To sequence the cloned gene

Answer

To express the cloned gene

Question 6

In gene expression, the promoter region plays a critical role. What is the primary function of a promoter?

Accepted Answer

To initiate the process of transcription

Answer

To terminate the process of transcription

Answer

To encode the amino acid sequence of a protein

Answer

To regulate the rate of transcription

Question 7

Bacteria have evolved various mechanisms to acquire genetic material from their surroundings. Which process is responsible for the uptake of exogenous DNA from the environment by bacteria?

Accepted Answer

Transformation

Answer

Transduction

Answer

Conjugation

Answer

Electroporation

Question 8

Which enzyme is responsible for generating the 'sticky ends' necessary for DNA ligation in cloning?

Accepted Answer

Restriction enzyme

Answer

DNA polymerase I

Answer

DNA ligase

Answer

DNA helicase

Question 9

In the context of bacterial gene expression, which type of vector is commonly employed to facilitate the production of recombinant proteins?

Accepted Answer

Plasmid

Answer

Cosmid

Answer

BAC

Answer

Phage

Question 10

Which technique is primarily used to identify specific DNA fragments of interest within a complex mixture?

Accepted Answer

Southern blotting

Answer

Polymerase chain reaction (PCR)

Answer

Gel electrophoresis

Answer

Microarray

Question 11

In genetic engineering, what is the primary function of a promoter?

Accepted Answer

To initiate transcription

Answer

To terminate transcription

Answer

To enhance translation

Answer

To cleave the DNA molecule

Question 12

Which of the following is NOT considered a potential application of recombinant DNA technology?

Accepted Answer

Remediation of oil spills

Answer

Production of therapeutic proteins

Answer

Development of genetically modified crops

Answer

Diagnostics for disease detection

Question 13

In recombinant DNA technology, what is the primary role of DNA ligase?

Accepted Answer

Joining of DNA fragments

Answer

Synthesis of new DNA strands

Answer

Cleavage of DNA molecules

Answer

Amplification of DNA

Question 14

What is the term used to describe the process of introducing recombinant DNA into a host cell?

Accepted Answer

Transformation

Answer

Transduction

Answer

Conjugation

Answer

Electroporation

Question 15

What is the primary purpose of a selectable marker gene in a plasmid vector?

Accepted Answer

To assist in the identification and isolation of transformed cells containing the plasmid

Answer

To provide a specific DNA sequence for gene cloning

Answer

To increase the stability of the plasmid

Answer

To regulate gene expression

Question 16

Which technique is commonly used to amplify specific DNA sequences in vitro for various applications?

Accepted Answer

Polymerase chain reaction (PCR)

Answer

Restriction digestion

Answer

DNA sequencing

Answer

Microarray analysis

Question 17

Which enzyme plays a crucial role in synthesizing the complementary strand of DNA during the polymerase chain reaction (PCR)?

Accepted Answer

DNA polymerase

Answer

RNA polymerase

Answer

Reverse transcriptase

Answer

Ligase

Question 18

In prokaryotic gene expression, what is the significance of the Shine-Dalgarno sequence?

Accepted Answer

Serves as the initiation site for ribosomes during translation

Answer

Acts as the promoter region for gene activation

Answer

Functions as the transcription termination site

Answer

Enhances gene regulation as an enhancer sequence

Question 19

Which technology provides a method for separating and analyzing DNA fragments based on their size?

Accepted Answer

Gel electrophoresis

Answer

Polymerase chain reaction (PCR)

Answer

Recombinant DNA technology

Answer

Hybridization

Question 20

What is the primary role of reverse transcriptase in molecular biology?

Accepted Answer

Synthesizes DNA using an RNA template

Answer

Synthesizes RNA using a DNA template

Answer

Breaks down DNA into smaller fragments

Answer

Joins DNA fragments together

Question 21

Which option is NOT a potential application of recombinant DNA technology?

Accepted Answer

Generation of nuclear energy through radioactive processes

Answer

Production of therapeutic proteins and pharmaceuticals

Answer

Gene therapy for treating genetic disorders

Answer

Forensic analysis for DNA identification

Question 22

In recombinant DNA technology, which enzyme is primarily responsible for precisely cutting DNA at specific sequences?

Accepted Answer

Restriction endonuclease

Answer

DNA polymerase

Answer

Ligase

Answer

Reverse transcriptase

Question 23

Why are bacterial plasmids often used as vectors in recombinant DNA technology?

Accepted Answer

They can replicate independently of the bacterial chromosome, allowing for efficient gene amplification.

Answer

They are always circular in structure, making them stable and easy to manipulate.

Answer

They are typically very large molecules, providing ample space for gene insertion.

Question 24

In gene cloning, what is the primary purpose of a selectable marker within the vector?

Accepted Answer

To identify bacteria that have successfully incorporated the recombinant plasmid.

Answer

To prevent the vector from degrading within the host cell.

Answer

To increase the efficiency of DNA ligation during vector construction.

Question 25

Which technique is used to amplify specific DNA sequences in vitro, enabling the creation of millions of copies from a small starting sample?

Accepted Answer

Polymerase Chain Reaction (PCR)

Answer

Southern blotting

Answer

Transformation

Answer

Gel electrophoresis

Question 26

What is an expression vector in the context of recombinant DNA technology?

Accepted Answer

A vector designed to allow the cloned gene to be transcribed and translated into a functional protein within the host cell.

Answer

A vector that carries a gene for antibiotic resistance, used for selecting transformed cells.

Question 27

Which of these is NOT a potential application of recombinant DNA technology?

Accepted Answer

Creating entirely new species of organisms through artificial gene synthesis.

Answer

Producing therapeutic proteins like insulin for treating diseases.

Answer

Developing genetically modified crops with enhanced traits like pest resistance.

Answer

Diagnosing genetic diseases by analyzing specific DNA sequences.

Question 28

What is the primary function of DNA ligase in the context of recombinant DNA technology?

Accepted Answer

To join together DNA fragments with compatible sticky ends, creating a continuous DNA molecule.

Answer

To cut DNA at specific sequences, generating fragments with sticky ends.

Answer

To copy DNA sequences, creating multiple copies of a target gene.

Question 29

A scientist has successfully introduced a gene into bacteria to produce a protein of interest. How would they verify the gene's integration and expression?

Accepted Answer

By using techniques like PCR to detect the presence of the gene and Western blotting to confirm the production of the protein.

Answer

By observing changes in the bacterial cell size and shape, indicating potential protein production.

Question 30

What is the main difference between a genomic library and a cDNA library?

Accepted Answer

A genomic library contains all DNA sequences from a genome, including non-coding regions, while a cDNA library only represents the expressed genes, reflecting the transcriptome.

Answer

A genomic library is constructed using plasmids, while a cDNA library uses bacteriophages as vectors.