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

Consider the following techniques/phenomena: (1) Budding and grafting in fruit plants (2) Cytoplasmic male sterility (3) Gene silencing

Which of above is/are used to create transgenic crops?

  1. 1 only

  2. 2 and 3

  3. 1 and 3

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

Transgenic crops are created using genetic engineering techniques. Cytoplasmic male sterility (CMS) is used in hybrid seed production, and gene silencing (including RNAi) is a key tool for creating transgenic traits like pest resistance. Budding and grafting are traditional vegetative propagation methods, not genetic engineering techniques for creating transgenics.

Multiple choice

Gene targeting is a technique utilising homologous recombination between an engineered exogenous DNA fragment and the genome of an individual's embryonic stem (ES) cells. Which of the following regarding this technique is INCORRECT?

  1. It uses homologous recombination to change an endogenous gene.

  2. The frequency of gene targeting can be significantly enhanced by using endonucleases.

  3. The targeting construct made out of DNA is generated in bacteria.

  4. Gene targeting is a permanent method.

  5. It requires the creation of a specific vector.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Gene targeting can be permanent or conditional. Conditions can be a specific time during development / life of the organism or limitation to a specific tissue.

Multiple choice

Which of the following statements does NOT characterise organisms as genetically engineered organisms containing recombinant DNA?

  1. Western hybridisation methods can be used to detect RNA and/or protein products.

  2. Recombinant DNA can have beneficial effects even if it is not expressed.

  3. The organisms containing recombinant DNA have apparently normal phenotypes.

  4. Additional phenotypes that are encountered include toxicity to the host organism.

  5. Inappropriate activation of previously unexpressed host cell genes can insert rDNA into chromosomal DNA.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In some cases, recombinant DNA can have deleterious effects even if it is not expressed. One mechanism by which this happens is insertional inactivation, in which the rDNA becomes inserted into a host cell's gene.

Multiple choice

Genetic engineering is the process of manually adding new DNA to an organism. Which of the following statements concerning the process of genetic engineering is false?

  1. The desired DNA is cleaved from the donating chromosome by the action of restriction enzymes.

  2. The desired DNA fragment is inserted into a vector, usually a viral particle, for transfer to the receiving chromosome.

  3. When the host cell reproduces, the vectors inside also reproduce.

  4. Gel electrophoresis is used to separate the remaining genes by movement on an electric grid.

  5. Radioactive probes are added in the gel electrophoresis, which attract and bind with the desired DNA to produce visible bands.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The desired DNA fragment is inserted into a vector, usually a plasmid, for transfer to the receiving chromosome. P lasmids are circular DNA molecules found in the cytoplasm of bacteria that bond with the desired DNA fragment with the help of the joining enzyme, DNA ligase, to create the resulting recombinant DNA.

Multiple choice

Which of the following pairs of ‘terminology: definition’ is not correctly matched?

  1. Biopiracy: illegal use of bio-resources

  2. RNA interference: a process to prevent infection of nematode in roots of tobacco plant

  3. Transgenic animals: animals that have manipulated DNA to possess and express an extra gene

  4. Bt: a bacterium that kills insects

  5. Biotic stress: a process of organisms growing on dead organisms
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Living organisms which can harm plants, such as viruses, fungi and bacteria and harmful insects are known as biotic stresses. The organisms which grown on dead organisms are called saprophytes like  bacteria, fungi, etc.

Multiple choice

Which of the following groups represents ‘approved transgenic crops’ only?

  1. Soybean, cotton, potato and chicory

  2. Soybean, cotton, maize and banyan

  3. Potato, chicory, banyan and poppy

  4. Poppy, amaltash, cotton and chicory

  5. Soybean, chicory, amaltash and poppy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Transgenic crops like - corn, tomato, soybean, cotton, potato, grapeseed, squash, beets, papaya, rice, flax, maize and chicory have been approved for commercial production in the USA. The most widely grown are “Bt” corn and cotton and glyphosate-resistant soybeans. Bt corn and cotton have had DNA from a naturally occurring insecticidal organism, Bacillus thurin-giensis, incorporated into their genome; it kills some of the most serious insect pests of these crops after they feed on the plant, while beneficial insects are left unaffected.

Multiple choice

Which one of the following terminologies is not correctly defined?

  1. PrP: A protein present in the arterial system of animals

  2. Pronuclear injection: The process of a fine needle to inject DNA into the nucleus of an unfertilized egg

  3. Resistance management: Strategies that can delay the onset of resistance

  4. Transgenic plants: Plants that have manipulated DNA to possess and express an extra gene

  5. Bt: A bacterium that attacks and kills insects
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Prion-related protein or PrP is a normal protein, expressed in the nervous system of animals, whose structure when altered (by interaction with altered copies of itself) is the cause of scrapie in sheep, BSE in cattle and Creutzfeldt-Jakob disease in humans.

Multiple choice

Assertion (A): Flavr Savr tomato was the first commercially grown genetically engineered food to be granted a license for human consumption. Reason (R): Flavr Savr tomatoes were developed using recombinant DNA techniques to express the trait of early softening of tomato fruit.

Directions: In the following question there are two statements, Assertion (A) and Reason (R), consider both the statements independently and mark your answers as under:
1. If A and R both are correct and R is correct explanation of A.
2. If A and R both are correct and R is not correct explanation of A.
3. If A is correct and R is incorrect.
4. If A is incorrect and R is correct.
5. If A and R both are incorrect.

  1. 1

  2. 2

  3. 3

  4. 4

  5. 5
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A is correct whereas R is incorrect. Flavr Savr, a genetically modified tomato, was the first commercially grown genetically engineered food to be granted a license for human consumption. Flavr Savr tomatoes were developed using recombinant DNA techniques to express the trait of delayed softening of tomato fruit.

Multiple choice

All of the following are mentioned in the passage as elements that are required for a successful gene therapy strategy EXCEPT that

Directions: This question is based on the following reading passage. Choose the best answer to the question on the basis of what is stated or implied in the passage.

Gene therapy offers a new treatment paradigm for curing human disease. Rather than altering the disease phenotype by using agents that interact with gene products, or are themselves gene products, gene therapy can theoretically modify specific genes resulting in disease cure following a single administration. Initially gene therapy was envisioned for the treatment of genetic disorders, but is currently being studied for use with a wide range of diseases, including cancer, peripheral vascular disease, arthritis, Neurodegenerative disorders and other acquired diseases.
Certain key elements are required for a successful gene therapy strategy. The most elementary of these is that the relevant gene be identified and cloned. Upon completion of the Human Genome Project, gene availability will be unlimited. Once identified and cloned, the next consideration must be expression of the gene. Questions pertaining to the efficiency of gene transfer and gene expression remain at the forefront of gene therapy research, with current debates revolving around the transfer of desired genes to appropriate cells, and then to obtaining sufficient levels of expression for disease treatment. With luck, future research on gene transfer and tissue-specific gene expression will resolve these issues for the majority of gene therapy protocols.
Other important considerations for a gene therapy strategy include a sufficient understanding of the pathogenesis of the targeted disorder, potential side effects of the gene therapy treatment, and a more in depth understanding of the target cells which are to receive gene therapy.
Gene transfer vector is the mechanism by which the gene is transferred into a cell. Currently there are at least 150 clinical gene therapy protocols worldwide. Since the approval process for these protocols is not as public outside the U.S., it is difficult to ascertain the exact number of worldwide protocols. As of December 1995, 1024 patients had been treated with either a gene transfer or gene therapy protocol. Much controversy exists regarding how many of these patients have benefited from their gene therapy, and no one has yet been cured.
Public controversy in the field of human gene therapy is driven by several factors. Ordinary citizens as well as scientists easily understand the enormous potential of gene therapy, but the former may not appreciate all the pitfalls and uncertainly that lie in the immediate future. The financial interests of biotechnology firms and, some have asserted, the career interests of some gene therapists have encouraged extravagant, or at least overly optimistic public statements about contemporary gene therapy. In spite of the proliferation of protocols, the actual number of patients treated remains small, and only one genuinely controlled study of human gene therapy has been published as of this date.

  1. identifying the relevant gene

  2. expressing the relevant gene

  3. determining the side effects of the relevant gene

  4. understanding of the pathogenesis of the targeted disorder

  5. gaining and a more in depth understanding of the target cells which are to receive gene therapy
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The best answer is (3). One must determine the side effects of the relevant gene therapy treatment, and not of the relevant gene itself.

Multiple choice

The application of genetic principles for the improvement of mankind is

  1. Genetic engineering

  2. Biotechnology

  3. Eugenics

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

Eugenics is the application of genetic principles to improve the human population through selective breeding and genetic intervention. Genetic engineering involves manipulating DNA, biotechnology uses biological processes for industrial applications, and anthropology studies human societies.

Multiple choice

The science that deals with the application of principles of heredity to the improvement of mankind is:

  1. Cell Biology

  2. Eugenesis

  3. Cytogenetics

  4. Plant genetics
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Eugenics is the science of applying principles of heredity to improve human genetic quality, though the term is now controversial due to historical misuse. Cell biology studies cell structure and function, cytogenetics combines cytology and genetics, and plant genetics specifically deals with heredity in plants - none of these focus on human improvement through heredity.

Multiple choice

Bt-cotton genes to repell:

  1. Bacterial pathogens

  2. Fungal pathogens

  3. Insect pests

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

Bt-cotton is genetically modified to express genes from Bacillus thuringiensis (Bt) that produce crystal proteins toxic to specific insect pests, particularly bollworms. It does not target bacteria, fungi, or nematodes. The Bt toxin specifically affects Lepidopteran larvae.

Multiple choice

Directions: Choose the most grammatically correct replacement for the underlined part. If ther is no error, choose that repeats the inderlined part.

Scientists have discovered that with genetic engineering, they would manipulate DNA so as to change hereditary traits.

  1. they can manipulate DNA so as to change hereditary traits.

  2. they will be able to manipulate DNA so as to change hereditary traits.

  3. they would manipulate DNA so as to change hereditary traits.

  4. they could manipulate DNA so as to change hereditary traits.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The only mistake in the sentence is the usage of “would” with plural form. The sentence is in past tense, hence 'can' is also incorrect, and therefore (D) is the correct option.