NEET Biotechnology and Its Applications Test

• Answer: (1) FISH
• Explanation: FISH uses fluorescent probes to locate specific DNA sequences on chromosomes.

• Answer: (1) Gel electrophoresis
• Explanation: Gel electrophoresis is used to separate DNA fragments by size, where smaller fragments move faster through the gel compared to larger ones.

• Answer: (2) Convert RNA into DNA
• Explanation: Reverse transcriptase synthesizes complementary DNA (cDNA) from an RNA template, commonly used in gene expression studies.

• Answer: (2) Oncomouse
• Explanation: The Oncomouse was genetically modified to carry an activated oncogene, making it a model for cancer research.

• Answer: (2) Northern blotting
• Explanation: Northern blotting detects RNA sequences using labeled probes, while Southern and Western blotting are used for DNA and proteins, respectively.

• Answer: (2) A mouse with a specific gene inactivated
• Explanation: Knockout mice are used in research to study the role of specific genes by inactivating them.

• Answer: (1) Agrobacterium
• Explanation: The first genetically modified plant was produced using Agrobacterium tumefaciens, which naturally transfers DNA to plant cells, making it a tool in plant genetic engineering.

• Answer: (4) All of the above
• Explanation: Gene therapy faces challenges like immune responses, limitations in treating complex disorders, and high costs.

• Answer: (1) Identical copies of a gene
• Explanation: Gene cloning generates multiple copies of the same gene, allowing for further study and application.

• Answer: (1) Polymerase Chain Reaction
• Explanation: PCR is a technique used to amplify specific DNA sequences, making millions of copies of a particular segment of DNA in a short time.

• Answer: (2) Vitamin A deficiency
• Explanation: Golden rice contains β-carotene, which the body converts into vitamin A, addressing vitamin A deficiency in developing countries.

• Answer: (4) All of the above
• Explanation: Transgenic animals serve in research, medicine, and agriculture for studying genes, creating therapies, and disease modeling.

• Answer: (4) The toxin causes cell wall damage to Bacillus thuringiensis.
• Explanation: Bt toxin is produced by Bacillus thuringiensis and is toxic to certain insects, not to the bacterium itself. The toxin disrupts the gut cells of insects, causing their death. It is also used in genetically modified crops to protect against pests.

• Answer: (1) Translation in nematode.
• Explanation: RNA interference (RNAi) is a process by which RNA molecules inhibit gene expression, typically by causing the degradation of mRNA or inhibiting its translation. In nematodes, RNAi primarily affects translation, thereby preventing the synthesis of certain proteins.

• Answer: (4) All of the above
• Explanation: These methods are commonly used in genetic engineering to introduce DNA into cells for transformation.

• Answer: (4) All of the above
• Explanation: Plasmids are circular DNA molecules used in cloning because they replicate independently, have selectable markers, and contain restriction sites for gene insertion.

• Answer: (1) Identify transformed cells
• Explanation: Selectable markers, such as antibiotic resistance genes, help identify cells that have taken up the plasmid vector.

• Answer: (4) All of the above
• Explanation: Techniques like RNAi, gene knockout, and antisense RNA prevent the expression of specific genes, silencing them.

Answer: (4) Ribosomes

Explanation: Ribosomes are cellular structures involved in protein synthesis and are not used as vectors for genetic engineering. Plasmids, phages, and transposons are commonly used as vectors.

• Answer: (2) Thermus aquaticus
• Explanation: Taq polymerase from Thermus aquaticus is used in PCR because it is stable at high temperatures.

• Answer: (4) All of the above
• Explanation: Bioinformatics integrates computational tools to analyze data in genomics, proteomics, and drug discovery.

• Answer: (2) DNA from two different sources combined
• Explanation: Recombinant DNA involves combining DNA from two different sources to create a new genetic combination used in genetic engineering.

• Answer: (1) Electroporation
• Explanation: Electroporation is a technique used to introduce recombinant DNA into cells by applying an electrical field, making the cell membrane temporarily permeable.

• Answer: (1) Escherichia coli
• Explanation: Human insulin is produced in Escherichia coli by inserting the human insulin gene into bacterial plasmids.

• Answer: (1) PCR
• Explanation: Polymerase Chain Reaction (PCR) is used to amplify specific DNA sequences rapidly.

• Answer: (2) Vitamin A
• Explanation: Golden rice is genetically modified to produce β-carotene, a precursor of vitamin A, to combat vitamin A deficiency in populations with limited access to this nutrient.

• Answer: (2) Cystic fibrosis
• Explanation: Gene therapy introduces a functional gene to correct genetic defects, such as those causing cystic fibrosis.

• Answer: (1) Enzyme-Linked Immunosorbent Assay
• Explanation: ELISA is a technique used to detect the presence of specific antigens or antibodies in a sample using enzyme-labeled immunoassay methods.

• Answer: (1) Escherichia coli
• Explanation: Recombinant DNA technology enables E. coli to produce human insulin by inserting the insulin gene into its genome.

• Answer: (1) Gel electrophoresis
• Explanation: Gel electrophoresis separates DNA fragments based on size using an electric field.

• Answer: (2) Exploitation of biological resources without permission
• Explanation: Biopiracy occurs when companies or researchers use indigenous biological resources without proper authorization or compensation.

• Answer: (2) They transfer genes into plants.
• Explanation: Ti plasmids, derived from Agrobacterium tumefaciens, are used in plant genetic engineering to transfer genes into plant cells.

• Answer: (1) It is used to create genetically modified organisms (GMOs).
• Explanation: Recombinant DNA technology is used to manipulate DNA and create GMOs by inserting genes from one organism into the DNA of another organism, making it widely applicable in agriculture, medicine, and research.

• Answer: (2) Synthesize DNA from RNA
• Explanation: Reverse transcriptase is an enzyme that synthesizes complementary DNA (cDNA) from an RNA template, commonly used in the study of gene expression.

• Answer: (1) They have foreign DNA integrated into their genome.
• Explanation: Transgenic organisms are those that contain DNA from a different species, integrated into their genome. This is a key feature in genetically modified organisms (GMOs).

• Answer: (2) Bacillus thuringiensis
• Explanation: Bt cotton is genetically modified to express a toxin from Bacillus thuringiensis that is lethal to specific insect pests.

• Answer: (1) Agrobacterium tumefaciens
• Explanation: Agrobacterium tumefaciens is a bacterium that is widely used for gene transfer in plants. It naturally transfers a portion of its DNA (T-DNA) into the plant genome, making it a “natural genetic engineer.”

• Answer: (4) All of the above
• Explanation: Plasmids, liposomes, and bacteriophages can all serve as vectors to deliver genetic material into host cells.

• Answer: (4) All of the above
• Explanation: These are types of genetic markers used to identify variations in DNA sequences for forensic and paternity analyses.

• Answer: (2) Modifying cells outside the body and reintroducing them
• Explanation: In ex vivo gene therapy, cells are removed from the patient, modified in the laboratory, and then reintroduced into the body.

• Answer: (3) Joining DNA fragments
• Explanation: DNA ligase is an enzyme used to join DNA fragments by forming phosphodiester bonds between the sugar-phosphate backbones of the DNA.

• Answer: (4) All of the above
• Explanation: Biotechnology improves agriculture through pest-resistant crops, biofertilizers, and transgenic plants with enhanced traits.

• Answer: (2) Reverse transcriptase
• Explanation: Reverse transcriptase synthesizes complementary DNA (cDNA) from mRNA, commonly used in molecular cloning and gene expression studies.

• Answer: (3) Cloning animals
• Explanation: While recombinant DNA technology has applications in insulin production, genetically modified crops, and gene therapy, animal cloning typically involves other techniques, such as somatic cell nuclear transfer.

• Answer: (4) All of the above
• Explanation: These crops were genetically engineered for specific purposes: pest resistance (Bt cotton), enhanced nutrition (Golden rice), and extended shelf life (Flavr Savr tomato).

• Answer: (2) It is synthesized from an RNA template.
• Explanation: cDNA (complementary DNA) is synthesized from an RNA template using reverse transcriptase and lacks introns.

• Answer: (4) All of the above
• Explanation: Selectable markers such as antibiotic resistance genes, fluorescent proteins, and reporter genes are used to identify cells that have successfully incorporated foreign DNA.

• Answer: (2) Herbert Boyer and Stanley Cohen
• Explanation: Boyer and Cohen pioneered recombinant DNA technology by combining DNA from different sources using restriction enzymes and ligase.

• Answer: (3) Restriction endonuclease
• Explanation: Restriction endonucleases are enzymes that cut DNA at specific sequences, a process that is crucial for cloning and recombinant DNA technology.

• Answer: (4) All of the above
• Explanation: Biofertilizers like Rhizobium, Azotobacter, and Mycorrhiza enhance soil fertility by fixing nitrogen or improving nutrient absorption.