Biotechnology is important part of science and its syllabus. Previous Year Question (PYQ) papers are invaluable resources for aspirants preparing for competitive exams like the Union Public Service Commission (UPSC) examinations. In this article we present important PYQ on Biotechnology.
PYQ on Biotechnology
Q- Consider the following statements: (2022)
- Biofilms can form on medical implants within human tissues.
- Biofilms can form on food and food processing surfaces.
- Biofilms can exhibit antibiotic resistance.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Statement 1: Biofilms are found extensively and can develop on practically all surfaces submerged in natural watery environments, such as water pipes, living tissue, tooth surfaces, implanted medical devices, and dental implants.
Statement 2: Various microorganisms have the capability to thrive on food matrices and within food industry infrastructure, leading to the creation of biofilms on food and food processing surfaces. For instance, Escherichia coli and Salmonella enterica are examples of such organisms. If Salmonella enterica contaminates a biofilm within a food pipeline, it can trigger significant outbreaks and pose severe health risks, particularly to children and the elderly.
Statement 3: A biofilm is a structured community of bacteria enveloped within a self-produced polymer matrix comprising polysaccharides, proteins, and DNA. Bacterial biofilms display increased resilience against antibiotics and disinfectants, as well as the ability to evade processes like phagocytosis, making them adept at causing persistent infections.
Q- Consider the following statements: DNA Barcoding can be a tool to: (2022)
- assess the age of a plant or animal.
- distinguish among species that look alike.
- identify undesirable animal or plant materials in processed foods.
Which of the statements given above is/are correct?
(a) 1 only
(b) 3 only
(c) 1 and 2
(d) 2 and 3
Answer- Option D
EXPLANATION
DNA barcoding is a technique used to rapidly and accurately identify species by analyzing a short segment of standardized gene regions and comparing the sequences to a reference database. It finds various applications such as:
- Identifying new species
- Assessing the safety of food
- Identifying and evaluating cryptic species
- Detecting alien or invasive species
- Identifying endangered and threatened species
- Linking egg and larval stages to adult species
- Protecting intellectual property rights for biological resources
- Developing global conservation management plans
- Identifying plant leaves even in the absence of flowers or fruits
- Identifying pollen collected by pollinating animals.
Q- Bollgard I and Bollgard II technologies are mentioned in the context of (2021)
(a) Clonal propagation of crop plants
(b) Developing genetically modified crop plants
(c) Production of plant growth substances
(d) Production of biofertilizers
Answer- Option B
EXPLANATION
Bollgard1 and Bollgard 2 are genetic modifications used in the development of crop plants. Bollgard cotton, engineered with these modifications, offers inherent protection against destructive Bollworm infestations. It incorporates an insecticidal protein sourced from Bacillus thuringiensis (Bt), a naturally occurring soil microorganism.
Bollgard Bt cotton, utilizing single-gene technology, was the first biotech crop technology approved for commercialization in India in 2002. On the other hand, Bollgard II technology employs a superior double-gene approach, featuring Cry1Ac and Cry2Ab genes, which offer enhanced protection against bollworms and Spodoptera caterpillars.
Q- Consider the following: (2021)
1. Bacteria
2. Fungi
3. Virus
Which of the above can be cultured in an artificial/ synthetic medium?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1,2 and 3
Answer- Option A
EXPLANATION
Statement 1: Bacteria have the ability to thrive in synthetic culture media. In a notable scientific breakthrough, researchers successfully re-engineered the DNA of Escherichia coli, resulting in a synthetic genome four times larger and more intricate than any previously constructed.
Statement 2: Fungi can also be cultivated in synthetic culture media. Notably, four fungi of allergological significance—Aspergillus fumigatus, Alternaria, Penicillium notatum, and Cladosporium herbarum—were cultured in a completely synthetic medium.
Statement 3: Viruses, unlike bacteria and fungi, lack their own metabolic machinery and thus rely entirely on host cells for replication. Consequently, viruses cannot be cultivated in synthetic culture media.
Q- Consider the following statements: (2021)
1. Adenoviruses have single-stranded DNA genomes whereas retroviruses have double-stranded DNA genomes.
2. Common cold is sometimes caused by an adenovirus whereas AIDS is caused by a retrovirus.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer- Option B
EXPLANATION
Adenoviruses are a prevalent group of viruses that commonly infect various parts of the body, including the eyes, airways, lungs, intestines, urinary tract, and nervous system. They are often responsible for symptoms such as fever, coughs, sore throats, diarrhea, and conjunctivitis (pink eye). While children are more susceptible to adenovirus infections, they can affect individuals of any age.
Statement 1: The genome of adenoviruses consists of a single linear molecule of double-stranded DNA, unlike retroviruses, which contain single-stranded DNA.
Statement 2: Adenoviruses are known to cause the common cold, while retroviruses such as HIV are responsible for infections like AIDS. HIV is classified as a retrovirus due to its possession of reverse transcriptase enzyme. It belongs to the D-type virus category within the Lentivirus family.
Q- Which of the following statements are correct regarding the general difference between plant and animal cells ? (2020)
(1) Plant cells have cellulose cell walls whilst animal cells do not.
(2) Plant cells do not have plasma membranes unlike animal cells which do.
(3) Mature plant cell has one large vacuole whilst an animal cell has many small vacuoles.
Select the correct answer using the code given below :
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option C
EXPLANATION
The primary distinction between plant and animal cells lies in the presence of a cell wall, which is unique to plant cells and provides mechanical support. Unlike animal cells, which lack cell walls, plant cells possess both a cell wall composed of cellulose and a cell membrane (plasma membrane). The cell wall functions as a rigid protective layer surrounding plant cells.
Additionally, plant cells feature a large central vacuole, which can occupy a significant portion of the cell’s volume, often up to 90%. In contrast, animal cells typically contain numerous smaller vacuoles that are considerably smaller than those found in plant cells. Therefore, statement 1 is accurate, while statement 2 is incorrect. Moreover, statement 3 is correct as it highlights the differences in vacuole size between plant and animal cells.
Q- In the context of recent advances in human reproductive technology, ‘Pronuclear Transfer” is used for (2020)
(a) Fertilization of egg in vitro by the donor sperm
(b) Genetic modification of sperm producing cells
(c) Development of stem cells into functional embryos
(d) Prevention of mitochondrial diseases in offspring
Answer- Option D
EXPLANATION
Pronuclear transfer is a technique involving the transfer of pronuclei from one zygote to another. The process begins with fertilization using healthy donated eggs from a mitochondrial donor and sperm from the intending male parent. Simultaneously, the intending mother’s affected oocytes are fertilized with sperm from the intending father. Once both sets of fertilized oocytes reach the early zygote stage, micromanipulation equipment is used to remove the pronuclei from the zygotes formed from donated eggs. These pronuclei are then discarded, and the resulting zygotes contain nuclear DNA from both intending parents and mitochondrial DNA from the donor.
Subsequently, the zygote is implanted into the mother’s uterus. Offspring produced through this method, combining the genetic material of one man and two women, are commonly referred to as “three-parent babies.” Pronuclear transfer is employed as a means to prevent the transmission of potentially debilitating mitochondrial diseases to offspring by reducing the effects of mutations occurring in mitochondrial DNA. This technology offers hope to women struggling with infertility and seeks to safeguard future generations from mitochondrial disorders.
Q- Consider the following statements : (2020)
(1) Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent.
(2) A person’s genome can be edited before birth at the early embryonic stage.
(3) Human induced pluripotent stem cells can be injected into the embryo of a pig.
Which of the statements given above is/are correct ?
(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Germline gene therapy involves transferring necessary DNA into reproductive cells, ensuring correction of disease-causing gene variants passed down through generations. Somatic cell gene therapy targets patient’s somatic cells, confining effects to the individual without inheritance. Genome editing enables altering DNA in various organisms, offering potential changes in physical traits and disease risk. A significant milestone was reached in 2017 when scientists corrected a disease-causing mutation in human embryos, advancing towards disease-free babies. While human-induced pluripotent stem cells show promise for regenerative medicine, attempts to grow human organs in pigs have yet to succeed, though injection of human-induced pluripotent cells into pig embryos has been demonstrated. Overall, gene therapies and genome editing hold promise for preventing and treating human diseases.
Q- Consider the following activities : (2020)
(1) Spraying pesticides on a crop field
(2) Inspecting the craters of active volcanoes
(3) Collecting breath samples from spouting whales for DNA analysis
At the present level of technology, which of the above activities can be successfully carried out by using drones ?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
A drone, also known as an unmanned aerial vehicle (UAV), is a device capable of flying without a human pilot onboard. Drones vary in their capabilities, with different types able to travel different distances and heights. Close-range drones, typically used for recreational purposes, can travel up to three miles.
Short-range drones, with a range of up to 90 miles, are often employed for espionage and intelligence gathering. Mid-range UAVs, with a distance range of 400 miles, find applications in intelligence gathering, scientific research, and meteorological studies. Endurance UAVs, capable of covering distances beyond 400 miles and reaching altitudes of up to 3,000 feet, serve various purposes including crop spraying. However, in India, the Ministry of Agriculture clarified that no approval has been granted for pesticide spraying using drones, despite their use by some farmers in the Southern region.
Q- ‘RNA interference (RNAi)’ technology has gained popularity in the last few years. why? (2019)
(1) It is used in developing gene silencing therapies.
(2) It can be used in developing therapies for the treatment of cancer.
(3) It can be used to develop hormone replacement therapies.
(4) It can be used to produce crop plants that are resistant to virtual pathogens.
Select the correct answer using the code given below.
(a) 1, 2 and 4
(b) 2 and 3
(c) 1 and 3
(d) 1 and 4 only
Answer- Option A
EXPLANATION
RNA interference (RNAi) technology gained prominence due to its application in gene silencing treatments associated with diseases like cancer. It involves utilizing double-stranded RNA to impede protein production in specific cells. Additionally, RNAi is utilized in developing genetically modified crop plants resistant to various plant viruses, including RNA and DNA viruses, viroids, insects, and fungal pathogens.
Q- Which of the following are the reasons for the occurrence of multi-drug resistance in microbial pathogens in India? (2019)
(1) Genetic predisposition of some people.
(2) Taking incorrect doses of antibiotics to cure diseases.
(3) Using antibiotics in livestock farming.
(4) Multiple chronic diseases in some people.
Select the correct answer using the code given below.
(a) 1 and 2
(b) 2 and 3 only
(c) 1,3 and 4
(d) 2,3 and 4
Answer- Option B
EXPLANATION
Multidrug resistance occurs when an organism develops resistance to multiple drugs. This resistance can be attributed to various factors such as incorrect antibiotic usage, extensive antibiotic use in livestock farming leading to antimicrobial resistance, inadequate sanitation, improper food handling, and poor infection control practices. These factors contribute to the transmission of antimicrobial-resistant bacteria from animals to humans, either directly or through the food chain and environment. However, genetic predisposition, which refers to inheriting genetic disorders or illnesses from parents, is not relevant to multidrug resistance.
Q- What is cas9 protein that is often mentioned in the news ? (2019)
(a) A molecular scissors used in targeted gene editing.
(b) A biosensor used in the accurate detection of pathogens in patients.
(c) A gene that makes plants pest-resistant
(d) A herbicidal substance synthesized in generally modified crops
Answer- Option A
EXPLANATION
CRISPR technology is a gene-editing tool that functions as molecular scissors for targeted gene editing. It involves scanning the genome to locate specific genetic sequences and then employing the Cas9 protein to precisely cut the DNA strands at those locations. Cas9, an enzyme derived from bacteria, acts as an RNA-guided endonuclease, recognizing and cleaving the targeted DNA with the guidance of RNA through base pairing.
Q- With reference to the Genetically Modified mustard (GM mustard) developed in India, consider the following statements : (2018)
(1) GM mustard has the genes of a soil bacterium that give the plant the property of pest-resistance to a wide variety of pests.
(2) GM mustard has the genes that allow the plant cross-pollination and hybridization.
(3) GM mustard has been developed jointly by the IARI and Punjab Agricultural University.
Which of the statements given above is/are correct ?
(a) 1 and 3 only
(b) 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Answer- Option B
EXPLANATION
The hybrid seed production of mustard involves the utilization of three genes obtained from Bacillus amyloliquefaciens, namely barnase, barstar, and bar. These genes, particularly barnase and barstar, facilitate cross-pollination and hybridization in mustard plants, which typically self-pollinate due to the presence of both male and female reproductive organs within individual flowers. The development of genetically modified (GM) mustard was spearheaded by researchers from Delhi University, with partial financial support from the Department of Biotechnology, a branch of the Ministry of Science.
Q- What is the application of Somatic Cell Nuclear Transfer Technology? (2017)
(a) Production of biolarvicides
(b) Manufacture of biodegradable plastics
(c) Reproductive cloning of animals
(d) Production of organisms free of diseases
Answer- Option C
EXPLANATION
Cloning involves creating an identical replica of a complete organism, another living component, or a cell. The technique known as Somatic Cell Nuclear Transfer (SCNT) was pioneered by Ian Wilmut and colleagues at the Roslin Institute in Edinburgh, resulting in the cloning of the sheep “Dolly” on July 5th, 1996, marking the first successful cloning of a mammal.
Recently, there has been groundbreaking news regarding the cloning of buffalos using adult somatic cells from high-quality males or females at the Central Institute for Research on Buffaloes (CIRB). This development represents a significant advancement, enabling the multiplication of superior buffalo germplasm within the country.
Q- With reference to agriculture in India, how can the technique of `genome sequencing’, often seen in the news, be used in the immediate future? (2017)
(1) Genome sequencing can be used to identify genetic markers for disease resistance and drought tolerance in various crop plants.
(2) This technique helps in reducing the time required to develop new varieties of crop plants.
(3) It can be used to decipher the host-pathogen relationships in crops.
Select the correct answer using the code given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Genome sequencing involves determining the sequence of DNA nucleotides, including adenine (A), cytosine (C), guanine (G), and thymine (T), within an organism’s genome. The human genome, for instance, comprises more than 3 billion of these genetic letters. This technique finds application in identifying genetic markers associated with disease resistance and drought tolerance in various crop plants.
Genome sequencing aids in genetic engineering, thereby expediting the development of new crop varieties. Additionally, it facilitates the understanding of host-pathogen interactions in crops.
Q- In the context of the developments in Bioinformatics, the term ‘transcriptome’, sometimes seen in the news, refers to (2016)
(a) a range of enzymes used in genome editing
(b) the full range of mRNA molecules expressed by an organism
(c) the description of the mechanism of gene expression
(d) a mechanism of genetic mutations taking place in cells
Answer- Option B
EXPLANATION
Bioinformatics involves the utilization of computer technology to handle biological data effectively. The transcriptome refers to the complete set of mRNA molecules generated within a specific cell or tissue type. Unlike the genome, which encompasses all DNA within a cell’s nucleus and mitochondria, the transcriptome represents the initial outcome of genome expression. Unlike the genome’s stability, the transcriptome is dynamic and subject to alterations influenced by various factors such as developmental stage and environmental cues.
Q- The Genetic Engineering Appraisal Committee is constituted under the (2015)
(a) Food Safety and Standards Act, 2006
(b) Geographical Indications of Goods (Registration and Protection) Act, 1999
(c) Environment (Protection) Act, 1986
(d) Wildlife (Protection) Act, 1972
Answer- Option C
EXPLANATION
The Genetic Engineering Appraisal Committee (GEAC) was established in accordance with the Environment Protection Act of 1986, with the Ministry of Environment and Forests serving as its overseeing ministry. Its primary role is to authorize projects that entail significant utilization of hazardous and recombinant materials in industrial processes. Additionally, it is tasked with evaluating and approving initiatives related to the introduction of genetically modified organisms and products into the ecosystem. Prior to the release of any genetically engineered organism into the environment, the committee conducts experimental field trials as part of its evaluation process.
Q- Recombinant DNA technology (Genetic Engineering) allows genes to be transferred (2013)
(1) Across different species of plants.
(2) From animals to plants.
(3) From microorganisms to higher organisms.
Select the correct Solution using the codes given below.
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Genetic engineering involves modifying the genetic material of an organism to change its characteristics, a process comprising three main steps: recombining DNA, gene cloning, and gene transfer. Recombinant DNA technology, as the name implies, combines DNA from different sources to create a new DNA sequence. This recombined DNA is then inserted into a host organism, resulting in a modified genetic makeup that may offer advantages over the original DNA. Integration typically occurs at a specific sequence called the origin of replication within the chromosome.
Essential tools for recombinant DNA technology include restriction enzymes (molecular scissors), cloning vectors, and competent hosts. The process involves several steps: isolating genetic material, cutting DNA at specific sites, amplifying the gene of interest using PCR, introducing the recombinant DNA into the host organism, obtaining the desired gene product, and performing downstream processing. Recombinant DNA technology finds applications across various fields, including science, agriculture, medicine, and industry.
Q- Mycorrhizal biotechnology has been used in rehabilitating degraded sites because mycorrhiza enables the plants to (2013)
(1) Resist drought and increase absorptive area
(2) Tolerate extremes of PH
(3) Resist disease infestation
Select the correct Solution using the codes given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Mycorrhiza is a mutually beneficial relationship between fungi and plants, facilitating plant growth and root development. This symbiosis enhances soil biology and chemistry, acting as a bio-fertilizer. There are two main types of mycorrhizae: endomycorrhizae, exemplified by orchids, and ectomycorrhizae, observed in pines and mushrooms.
Fungi exhibit resilience to diverse environmental conditions, including pH extremes, high temperatures, and heavy metal toxicity. They contribute to plant health by increasing nutrient availability and aiding in drought and salinity resistance. Additionally, fungi play roles in disease prevention, phosphorus absorption, and soil erosion control, ultimately leading to improved soil quality and organic matter content.