Biology

Genetic Engineering and Biotechnology

2,033 Questions

Genetic engineering and biotechnology involve modifying organism DNA to develop transgenic crops, medical treatments, and industrial solutions. This field covers essential techniques like hybridoma technology, molecular markers, and gene transfer in eukaryotic cells. These biology topics are essential for aspirants preparing for various competitive examinations.

Genetic engineering techniquesTransgenic organismsIndustrial biotechnologyGMOs and bioremediation

Genetic Engineering and Biotechnology Questions

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

The most extensively used bacteria in genetic engineering is ____________.

  1. Bacillus

  2. Clostridium

  3. Escherichia

  4. Salmonella
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Escherichia coli (E. coli) is the most widely used host organism in genetic engineering due to its well-understood genetics and ease of culture.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Which of the following is not a method of introducing alien DNA into host cells?

  1. Micro injection

  2. Electroporation

  3. Being placed along with the cell into a gene gun

  4. Gel electrophoresis
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A. Microinjection is a technique in which DNA is directly injected into the host cells with the help of microinjection.
B. Electroporation is a technique in which pores are created in the cell membrane and thus, permeability is increased. As a result, foreign DNA can easily enter the cells.
C. Gene gun is a method to introduce alien DNA into host cells through microprojectile particles. The DNA coated gold or tungsten particles are bombarded with the host cells and alien DNA enters the cells.
D. Gel electrophoresis is a technique of separating DNA fragments on the basis of their size.
Hence, option D is not a method of introducing alien DNA into host cells.
So, the correct answer 'Gel electrophoresis'.
Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Identify the correct sequence of steps in the construction of recombinant DNA.
$(1)$ use restriction enzymes
$(2)$ use DNA ligase
$(3)$ remove plasmid from parent bacterium
$(4)$ introduce plasmid into new host bacterium.

  1. $1-2-3-4$
  2. $4-3-2-1$
  3. $3-1-2-4$
  4. $2-3-1-4$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Generation  of rDNA steps:
1) The DNA for insulin is first disengaged. 
2) A plasmid made of DNA is expelled from a bacterial cell. 
3) A limitation protein cuts the plasmid DNA open, leaving sticky finishes. 
4) The insulin quality, with integral sticky closures, is included. 
5) DNA ligase catalyst grafts (joins) together with the plasmid DNA and the Insulin DNA. 
6) The plasmid (now hereditarily changed) is embedded again into the bacterium. 
7) The bacterium has cell, partitions and delivers duplicates of the plasmid. 
8) The Bacterium makes human insulin utilizing the quality in the plasmid. 
9) The insulin is removed from the bacterial culture.
So, the correct option '2−3−1−4'.
Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

The process by which restriction endonuclease cut the DNA molecule?

  1. Reduction

  2. Oxidation

  3. Hydrolysis

  4. Carboxylation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Restriction endonucleases are enzymes that cleave the phosphodiester bonds between nucleotides within a polynucleotide chain. This bond breakage is achieved through the addition of a water molecule, which is a hydrolysis reaction.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

The technique in which a foreign DNA is precipitated on the surface of the tungsten or gold particle and shot into target cells is known as? 

  1. Microinjection

  2. Chemical - mediated genetic transformation

  3. Electroporation

  4. Biolistic method
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The biolistic method, or gene gun technique, coats microscopic gold or tungsten particles with foreign DNA and accelerates them at high velocity into target cells. Microinjection directly injects DNA into the nucleus using a micropipette.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Which one of the following is commonly used in transfer of foreign DNA into crop plants?

  1. Penicillium expansum

  2. Trichoderma harzianum

  3. Meloidogyne incognita

  4. Agrobacterium tumefaciens
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Trichoderma harzianum is a biofungicide and is used for suppression of various disease causing fungal pathogens. Penicillium expansum, blue mold, causes postharvest decay of stored apples and produces the carcinogenic mycotoxin patulin. Meloidogyne incognita, southern root-knot nematode" or the "cotton root-knot nematode", is a nematode with multiple hosts. Agrobacterium tumefaciens is a soil plant pathogenic bacterium that carries Ti plasmid. It can transfer a particular segment of the tumor-inducing (Ti) plasmid into the nucleus of infected cells. The transferred T-DNA is then integrated into the host genome and transcribed with it. This ability of Agrobacterium tumefaciens to transfer the T-DNA in host genome is explored in genetic engineering to transfer the desired DNA segment, carrying the gene of the interest, into genome of selected organisms. Option D is the correct answer. 

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Which one of the following is called polynucleotide joining enzyme?

  1. Polymerase I

  2. Polymerase II

  3. Ligase

  4. Ribonuclease
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ligase is nick named as 'molecular sutures'. In Biochemistry, ligase is defined as an enzyme that can catalyze the joining of two large molecules by forming a new chemical bond.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Read the following four statements (A-D) about certain mistakes in two of them:

(A) The first transgenic buffalo, Rosie produced milk which was human alpha-lactalbumin enriched.
(B) Restriction enzymes are used in isolation of DNA from other macro-molecules.
(C) Downstream processing is one of the steps of r-DNA technology.
(D) Disarmed pathogen vectors are also used in transfer of r-DNA into the host.

Which are the two statements having mistakes?

  1. Statements (A) and (B)

  2. Statements (B) and (C)

  3. Statements (C) and (D)

  4. Statements (A) and (C)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

(A) Rosie was the first transgenic cow and its milk was rich in human alpha-lactalbumin protein.

(B) Restriction enzymes are used in the isolation of the specific segment of DNA from the DNA of the organism because these enzymes are capable of cutting the DNA at the specific location.
(C) Downstream processing is one of the steps in the r-DNA technology. It involves the extraction and purification of the desired product.
(D) Disarmed pathogens like Agrobacterium tumifaciens, phage viruses are also used in the transfer of r-DNA into the host.
Hence, the correct answer is '(A) and (B)'

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

A dicotyledonous plant forms crown gall when

  1. Agrobacterium tumefaciens comes in contact with the plant

  2. Agrobacterium rhizogenes comes in contact with the plant

  3. A specific part of DNA from the Ti plasmid gets integrated with the plant chromosome

  4. A specific part of DNA from the Ri plasmid gets integrated with the plant chromosome
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Crown gall disease is caused by Agrobacterium tumefaciens, which transfers a specific segment of its Ti plasmid (T-DNA) into the plant genome.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Consider the following steps during recombinant DNA technology.
a. Breaking of donor DNA using restriction enzyme
b. Culture of cloned bacteria containing the fragment of donor DNA
c. Isolation of suitable plasmid
d. Insertion of recombinant DNA through cloning
e. Joining of donor DNA with a suitable plasmid using ligase
The correct sequence of these is?

  1. $1, 3, 2, 4, 5$
  2. $3, 2, 1, 5, 4$
  3. $1, 3, 5, 4, 2$
  4. $5, 1, 3, 4, 2$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The correct chronological sequence of recombinant DNA technology steps is: first isolate the suitable plasmid (c), break the donor DNA using restriction enzymes (a), join the donor DNA with the plasmid using ligase to form recombinant DNA (e), insert the recombinant DNA into a host through cloning (d), and finally culture the transformed bacteria (b). This matches the sequence 1, 3, 5, 4, 2 if steps a, c, e, d, b correspond to those numbers.

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

Which of the following tools of recombinant DNA technology is incorrectly paired with its use?

  1. Reverse transcriptase-production of.cDNA from mRNA

  2. DNA polymerase-used in polymerase chain reaction to amplify section of DNA

  3. DNA ligase-enzyme that cuts DNA, creating the sticky ends of restriction fragments

  4. Restriction enzyme-production of RFLPs
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Restriction enzymes cut DNA creating sticky ends of restriction fragments. While DNA ligase joins these sticky ends to form recombinant DNA. 

So, the correct option is 'DNA ligase-enzyme that cuts DNA, creating the sticky ends of restriction fragments'. 

Multiple choice botany option b: biotechnology and bioinformatics insertion and ligation of dna cutting, insertion and ligation of dna biotechnology in agriculture

After insertion of DNA segment within the sequence of Z-gene of bacteria, they are grown on chromogenic substrate. After the growth of bacterial colonies, they are identified as
i) Recombinants if colonies are blue- coloured.
ii) Recombinants if colonies are white coloured.
iii) Non-recombinants if colonies are blue- coloured.
iv) Non-recombinants if colonies are white coloured.

  1. iii, iv

  2. i, iv

  3. i, ii

  4. ii, iii
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In insertional inactivation, the Z-gene (encoding beta-galactosidase) is disrupted. If the gene is intact, the bacteria produce the enzyme and turn blue on chromogenic substrate (non-recombinant). If the DNA segment is inserted, the enzyme is not produced, and colonies remain white (recombinant).

Multiple choice zoology applications of biotechnology cloning process of cloning gene cloning

Cloning is a method to

  1. Replace original genotype

  2. Preserve genotype

  3. Production of HGH gene in Escherichia coli

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cloning is the process of producing genetically identical copies of a biological entity. Therefore, its primary purpose is to preserve the genotype of the original organism.

Multiple choice zoology applications of biotechnology cloning process of cloning gene cloning

Which one of the following is used as vector for cloning genes into higher organisms? 

  1. Rhizopus nigricans

  2. Retrovirus

  3. Baculovirus

  4. Salmonella typhimurium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Salmonella (S.) typhi is an important intracellular pathogen, exclusively for humans  that causes typhoid or enteric fever that make most suitable as a vaccine vector carrying antigens of other pathogens. The hybrids are studied for  induced immune response against response to both the Salmonella bacteria and the antigen of the pathogen in under study.
  • Retroviral vectors are created by replacing retroviral gag, pol, and env genes with therapeutic gene and used in gene therapy which is the process of introduction of DNA into living human beings in order to treat disease. It is used to replace a missing gene product or to correct mutant alleles.
  • Baculoviruses have rod-shaped capsids and large, double-stranded DNA genomes that infect insects. Their polyhedrin gene is replaced with foreign DNA which is expressed at high levels under the control of the endogenous polyhedrin promoter and is mainly used for high-level transient protein expression in insects and insect cells.
  •  Rhizopus nigricans is used as host vector system for mass synthesis of protein encoded by gene cloned in plasmid vectors.
  • So, the correct answer is 'Retrovirus'.