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Q1. What are transgenic animals? Explain any four ways in which such animals can be beneficial to humans.

Solution

The organisms which contain functional foreign genes experimentally introduced into their genome by genetic engineering from another species are called transgenic animals. Benefits of transgenic animals: 1. Study of normal physiology and development: Transgenic animals are useful to study gene regulation, their effect on the normal functioning of the body and its development. 2. Study of diseases: Transgenic models have been developed for many human diseases like cancer, cystic fibrosis, rheumatoid arthritis and Alzheimer’s disease. 3. Vaccine safety: Transgenic mice have been developed to test the safety of vaccines before they are being used on humans. 4. Chemical safety testing: Transgenic animals are made to carry genes which make them more sensitive to the toxic substances than non-transgenic animals. On exposure to the toxic substances, their effects can be studied in a lesser time.

Q2. Hybridoma technology has been successfully used in

• 1) Production of somatic hybrids
• 2) Synthesis of monoclonal antibodies
• 3) Production of alcohol in bulk
• 4) Synthesis of haemoglobin

Solution

Hybridoma technology is a technique of forming hybrid cell lines (hybridomas) by fusing a specific antibody producing B cell with a myeloma (cancerous B cell) cell that is selected for its ability to grow in tissue culture and for the absence of antibody chain synthesis. The antibodies produced by the hybridoma are all of a single specificity and are therefore referred to as monoclonal antibodies.

Q3. In the process of blood clotting, TPA stands for

• 1) Tissue Platelet Activator
• 2) Tissue Protein Anchor
• 3) Tissue Plasminogen Activator
• 4) Tissue Protection Agent

Solution

TPA stands for Tissue Plasminogen Activator, which helps in the breakdown of blood clots.

Q4. The term ‘Humulin’ is used for

• 1) Human insulin
• 2) Hydrolytic enzyme
• 3) Isoenzyme
• 4) Antibiotic

Solution

The genetically engineered E. coli that could make human insulin was developed by a company called Genetech in 1978. This technique was purchased by another American company Eli Lilly in September in 1982. On July 5 1983, Eli Lilly launched the first genetically engineered human insulin by the name Humulin. 

Q5. cDNA stands for

• 1) Constricted DNA
• 2) Complementary DNA
• 3) Constructed DNA
• 4) Circular DNA

Solution

cDNA means complementary DNA. It is a double-stranded DNA molecule synthesised from an RNA molecule.

Q6. Which of the following is used in the treatment of certain kinds of cancer?

• 1) Interleukin
• 2) Tumour necrosis factor
• 3) All of the above
• 4) Interferon

Solution

In certain kinds of cancer, interferons, interleukins and tumour necrosis factor are used.

Q7. Which Indian variety of rice was patented by an American company?

• 1) Basmati
• 2) Clearfield
• 3) Tukda
• 4) Komal

Solution

The American rice company Rice Tec. Inc. patented Basmati rice, which is an Indian variety of rice.

Q8. Insulin is made of two chains—chain A and chain B. Chain A is made of how many amino acids?

• 1) 10
• 2) 11
• 3) 21
• 4) 20

Solution

Insulin is made of two chains—chain A and chain B. Chain A comprises 21 amino acids and chain B comprises 30 amino acids.

Q9. Transplantation of organs from an organism of one species to an organism of another species is known as

• 1) Exotransplantation
• 2) Endotransplantation
• 3) Xenotransplantation
• 4) Protransplantation

Solution

Transplantation of organs from an organism of one species to an organism of another species is known as xenotransplantation.

Q10. Which of the following is an advantage of transgenesis?

• 1) All of the above
• 2) Vaccine safety testing
• 3) Increased production of biological products
• 4) Study of diseases and gene therapy

Solution

Significance of transgenesis: 1. Molecular farming 2. Study of diseases and gene therapy 3. Increased production of biological products 4. Study of normal physiology and development 5. Vaccine safety testing 6. Chemical safety testing

Q11. In India, it is common knowledge that _____ is used for the control of diabetes.

• 1) Karela
• 2) Bengan
• 3) All of the above
• 4) Jamun

Solution

In India, it is common knowledge that karela, bengan and jamun are used for the control of diabetes.

Q12. A transgenic food crop which may help in solving the problem of night blindness in developing countries is

• 1) Golden rice
• 2) Flavrsavr tomatoes
• 3) Starlink maize
• 4) Bt soybean

Solution

Golden rice was developed at Swiss Federal Institute of Technology. It is rich in Vitamin A. The rice grains are golden yellow in colour and contain beta carotene from daffodil plant and the genes from some bacteria. Consumption of golden rice may reduce the risk of night blindness caused due to the deficiency of vitamin A among children. Bt soybean confers insect and pest resistance of soybean crops. Flavrsavr tomatoes show delayed ripening and prevent rotting and spoilage of tomatoes caused during shipping and transportation. Starlink maize possesses Cry protein that offers resistance to the attack of caterpillars.

Q13. The Neem Campaign was led by

• 1) Vandana Shiva
• 2) Shiva Bhosle
• 3) Kiran Mittal
• 4) Durga Mehta

Solution

The Neem Campaign by Vandana Shiva led to the cancellation of a European patent to a transnational corporation for pesticide from neem. 

Q14. Insect control proteins are extracted from which of the following organisms?

• 1) Pseudomonas
• 2) Bacillus thuringiensis
• 3) Trichoderma
• 4) Penicillium

Solution

Bacillus thuringiensis produces certain proteins which when ingested by insects kills them. Hence, Bacillus thuringiensis is usedto produce endotoxins against insects. 

Q15. For which variety of Indian rice was a patent filed by a USA Company?

Solution

Indian Basmati crossed with a semi-dwarf variety was claimed as a new variety, for which the patent was filed by a USA company.

Q16. Flavr Savr is genetically modified

• 1) Tomato
• 2) Rice
• 3) Banana
• 4) Potato

Solution

Flavr Savr is genetically modified tomato, which is modified to produce less amounts of polygalacturonase, a cell wall-degrading enzyme. This increases the shelf life of the fruit.

Q17. Insect resistance transgenic cotton has been produced by inserting a piece of DNA from

• 1) An insect
• 2) A virus
• 3) A bacterium
• 4) A wild relative of cotton

Solution

The gene (cry gene) responsible for the production of toxin (Bt toxin) has been isolated from Bacillus thuringiensis and introduced into a new number of crop plants using Agrobacterium Ti plasmid mediated transformation. The new genetically modified Bt cotton is resistant to the bollworm complex.

Q18. The primary steroid which gives rise to male and female sex hormones is

• 1) Estradiol
• 2) Dexamethasone
• 3) Cholic acid
• 4) Cholesterol

Solution

Cholesterol is a primary steroid from which male and female sex hormones are derived.

Q19. How do interferons protect us?

Solution

Interferons protect non-infected cells from further viral infections by creating cytokine barriers. They also inhibit cellular proliferation and modulate the immune system of the organism.

Q20. You have identified a useful gene in bacteria. Make a flow chart of the steps that you would follow to transfer this gene to a plant.

Solution

After identifying a useful gene in bacteria, following steps should be undertaken to transfer the gene to a plant:                  

Q21. Why do the toxic insecticidal proteins secreted by Bacillus thuringiensis kill the insect and not the bacteria itself?

Solution

The Bt toxin protein exists as inactive protoxin. Once an insect ingests the inactive toxin, it is converted into an active form of the toxin due to the alkaline pH of the gut which solubilises the crystals. Therefore, it does not kill the bacteria.

Q22. What is legally wrong in the US patent law? Mention the common items of biopiracy.

Solution

US patent law does not recognise technologies and methods in use to other countries as 'prior past'. The common items of biopiracy are soil micro-organisms plants, animals and their genetic material.

Q23. Oral contraceptives contain

• 1) Oestrogen and progesterone
• 2) Progesterone
• 3) Oestrogen
• 4) Prostaglandins

Solution

Oral contraceptives contain both oestrogen and progesterone.

Q24. Injecting cows with bovine growth hormone causes

• 1) Increased milk and decreased beef output
• 2) Increased beef output
• 3) Increased milk production
• 4) Increased milk and beef output

Solution

Injecting cows with bovine growth hormone obtained from genetically engineered E. coli raises the milk and beef output in the cows.

Q25. How does RNA interference help in developing resistance in tobacco plant against nematode infection?

Solution

A nematode Meloidegyne incognitia infects the roots of tobacco plants which reduce the production of tobacco. The infection can be prevented using RNA interference (RNAi) process which is checked by silencing of specific mRNA due to a complementary ds RNA. The ds RNA binds and prevents translation of the mRNA. By using Agrobacterium vectors, nematode-specific genes were introduced into the host plants which produce both sense and antisense RNA in the host cells. These two RNAs are complementary to each other and form a double stranded RNA (ds RNA) that initiates RNAi and hence, silences the specific mRNA of the nematode. The parasite cannot survive in transgenic host and so, prevents the plants from pests.

Q26. List three molecular diagnostic techniques that help detect pathogens from suspected patients. Mention one advantage of these techniques over conventional methods.

Solution

Molecular diagnostic techniques that help to detect pathogens from suspected patients are: (a) Recombinant DNA technology (b) Polymerase chain reaction (PCR) (c) Enzyme linked immune sorbent assay (ELISA) These techniques are better than the conventional methods because they help in early diagnosis of the disease and give precise results even when the bacteria or virus concentration is very low.

Q27. The first clinical gene therapy was done for the treatment of

• 1) SCID (Severe Combined Immuno Deficiency resulting from deficiency of ADA)
• 2) AIDS
• 3) Cystic fibrosis
• 4) Cancer

Solution

Treatment of a genetic disorder by manipulating genes is called gene therapy. The first clinical gene therapy was done for the treatment of SCID. The SCID patient has a defective gene for the enzyme adenosine deaminase (ADA). The patient lacks functional lymphocytes and therefore, fails to fight the infecting pathogens. Lymphocytes are extracted from the patient’s bone marrow and a normal functional copy of human gene coding for ADA is introduced into these lymphocytes with the help of retrovirus. The cells so treated are reintroduced into the patient’s bone marrow. The lymphocytes produced by these cells contain functional ADA gene, and reactivate the patient’s immune system permanently.

Q28. In India, GEAC is an organisation which was set up by the government to regulate biotechnological activities and to keep the activities under ethical limits. This organisation was set up by which ministry of the government?

• 1) Health Ministry
• 2) Ministry of Environment and Forests
• 3) Education Ministry
• 4) Ministry of Defence

Solution

GEAC (Genetic Engineering Approval Committee) was set up by the Ministry of Environment and Forests to regulate the research, testing and commercial release of genetically modified crops, food and organisms.

Q29. RuBisCO acts on

• 1) Both CO_2­ and O₂
• 2) CO₂
• 3) O₂
• 4) Neither CO­₂ nor O_2­

Solution

RuBisCO or ribulose 1,5-bisphosphate can act on both carbon dioxide and oxygen.

Q30. The hybridoma technique was developed by

• 1) Edward Jenner
• 2) Kohler and Milstein
• 3) Louis Pasteur
• 4) Burnet

Solution

Hybridoma technology is a technique of forming hybrid cell lines (hybridomas) by fusing a specific antibody producing B cell with a myeloma (cancerous B cell) cell that is selected for its ability to grow in tissue culture and for the absence of antibody chain synthesis. It was introduced by Georges Kohler and Cesar Milstein in 1970. Louis Pasteur discovered the principles of vaccination, microbial fermentation and pasteurization. Edward Jenner discovered the vaccine for smallpox. John Burnet was a classicist and is known for his work on philosophy.

Q31. The only commercially grown genetically modified crop in India is

• 1) Barley
• 2) Rice
• 3) Wheat
• 4) Cotton

Solution

The only commercially grown genetically modified crop in India is cotton.

Q32. Name any five transgenic plants and their potential applications.

Solution

Some transgenic plants and their potential applications are given below:   Transgenic plants Applications 1. Bt cotton Resistance to bollworm infestation, tolerance to herbicide, high yielding 2. Golden rice Rich in vitamin A 3. Brassica napus Contains hirudin that prevents blood clotting 4. Flavr Savr tomato Better nutrient quality and longer shelf life 5. Maize Herbicide resistance    

Q33. Write two uses of PCR technique in molecular diagnosis.

Solution

Two uses of PCR technique in molecular diagnosis: (i) It is used to detect HIV in suspected AIDS patients. (ii) It is used to detect mutations in the gene of suspected cancer patients.

Q34. Why is the gene encoding for Cry protein inserted into a crop plant?

Solution

The gene encoding for Cry protein is inserted into a crop plant to provide resistance against insect larvae.

Q35. Highlight any four advantages of genetically modified organisms (GMOs).

Solution

Advantages of genetically modified organisms (GMOs): (i) Tolerant to abiotic stresses (cold, drought, salt, heat) (ii) Reduces reliability on chemical pesticides (iii) Reduces post-harvest losses (iv) Increases efficiency of mineral usage by plants

Q36. Mention the source organism of the gene cryIAc and its target pest.

Solution

Source organism: Bacillus thuringiensis Target pest: Cotton bollworms

Q37. What are the conditions for which patent is given?

Solution

Government grants patent to certain inventors as permission to use invention for commercial purpose. Patent is given for the following reasons: 1. For producing new product or invention 2. Modified or improved earlier invention 3. Technical know how 4. New designing concept