Telangana TSBIE TS Inter 2nd Year Botany Study Material 12th Lesson Biotechnology and its Applications Textbook Questions and Answers.
TS Inter 2nd Year Botany Study Material 12th Lesson Biotechnology and its Applications
Very Short Answer Type Questions
Expand GMO. How is it different from a hybrid?
- GMO means Genetically Modified Organisms.
- Hybrids are new crop varieties produced by crossing two genetically different parents whereas GMO are plants, bacteria, fungi or animals whose genes have been altered by manipulation.
Give different types of cry genes and pests which are controlled by the proteins encoded by these genes.
- Genes Cry I Ac and Cry II Ab control the cotton bollworms.
- Genes Cry I Ab controls corn borer.
Can a disease be detected before its symptoms appear? Explain the principle involved. [Mar. 2019, 2017]
- Yes, very low concentration of Bacteria or virus can be detected by amplification of their nucleic acids through PCR.
- ELISA is used to detect infection by a pathogen based on the principle of antigen-antibody interaction.
Many toxic proteins are produced in their inactive form by micro-organisms. Explain how the mechanism is useful for the organism producing the toxin.
- The Bt toxin proteins exist as inactive protoxins but once an insect ingests the inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut which solubilises the crystals.
- The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause swelling and lysis and eventually cause the death of the insect.
Why has the Indian parliament cleared the second amendment of the country’s patents bill?
- Amendment of the Indians patents bill by the Indian parliament, prevents unauthorized exploitation of their bioresources and traditional knowledge.
- It also considers patent terms, emergency. Provisions and research and development initiatives.
Give any two reasons why the patent on Basmati should not have gone to an American company. [May 2014]
- Basmatic rice is distinct for its Unique aroma and flavour and 27 documented varieties of Basmati are grown in India.
- There is reference to Basmati in ancient texts, forklore and poetry, as it has been grown in India for centuries. The new variety of Basmati produced by American company had actually been derived from Indian farmers variety.
PCR is a useful tool for early diagnosis of an infectious disease. Elaborate.
- The very low concentration of a bacteria or virus can be detected by amplification of their nucleic acid through PCR.
- PCR is now used to detect HIV in suspected AIDS patient. It is used to detect mutations in genes, in suspected cancer patients too. It is a powerful technique to identify many genetic disorders.
What is GEAC and what are its objectives? [Mar. ’18, ’14; May ’17]
- GEAC – Genetic Engineering Approval Committee, established by Govt, of India.
- It make decisions regarding the validity of GM research and the safety of introducing GM organisms for public services.
Name the nematode that infects the roots of tobacco plants. Name the strategy adopted to prevent this infestation.
- A nematode, Meloidegyne incognitia infects the roots of tobacco plants and causes a great reduction in yield.
- This infestation can be prevented based on the process of RNA interference (RNAi).
For which variety of Indian rice, has a patent been filed by a USA company.
- Basmati variety of rice with unique aroma and flavour.
- Indian Basmati was crossed with semi dwarf varieties and claimed as an invention (a novelty) by an American company for patent in 1997.
Give one example for each of transgenic plants which are suitable for food processing and those with improved nutritional quality. [Mar. 2020]
- Transgenic tomato ‘Flavr Savr’ is bruise resistant, i.e., suitable for storage and transport due to delayed ripening and offers longer shelf life.
- Transgenic golden rice obtained from “Taipei” is rich in vitamin A and prevents blindness.
Short Answer Type Questions
List out the beneficial aspects of transgenic plants. [March 2019, Mar. ’18; May ’17, ’14]
Beneficial aspects of transgenic plants are
I. Transgenic crop plants having resistance to pathogens and pests :
- Transgenic papaya is resistant to papaya ring spot virus.
- Bt. cotton is resistant to insects.
- Transgenic tomato plants are resistant to the bacterial pathogen pseudomonas.
- Transgenic potato plants are resistant to the fungus phytophthora.
II. Transgenic plants suitable for food processing technology :
Transgenic tomato ‘Flavr Savr’ is bruise resistant i.e., suitable for storage and transport due to delayed ripening and offers longer shelf life.
III. Transgenic plants with improved nutritional value :
Transgenic golden rice obtained from ‘Taipei’ is rich in vitamin A and prevents blindness.
IV. Transgenic plants useful for hybrid seed production :
Male sterile plants of Brassica napus are produced. This will eliminate the problem of manual emasculation and reduce the cost of hybrid seed production.
V. Transgenic plants tolerant to abiotic stresses caused by chemicals, cold, drought, salt, heat etc.
- Basmati variety of rice was made resistant against biotic and abiotic stresses.
- Round up ready soyabean is herbicide tolerant.
What are some bio-safety issues concerned with genetically modified crops? [March 2017, 2014]
Biosafety issues concerned with genetically modified crop are :
- There is fear of transferring allergins or toxins to humans and animals as side effects.
- There is a rick of changing the fundamental nature of vegetables.
- They may pose a harmful effect on biodiversity and have an adverse impact on environment.
- There is a risk of gene pollution due to transfer of the new genes into related wild species through natural out-crossing. This may result in the development of super weeds which may be fast growing than the crops and may be resistant to weedicides.
- They may bring about changes in natural evolutionary pattern.
Give a brief account of A) Bt. cotton [Mar. 2020]
B) Pest resistant plants
A) Bt Cotton :
Bt cotton is created by using some strains of a bacterium, Bacillus thuringiensis (Bt is short form).
- This bacterium produces protein that kill certain insects such as lepidopterans (tobacco, bud worm, army worm), coleopterans (beetles) and dipterans (flies, mosquitoes).
- B.thuringiensis forms protein crystals during a particular phase of growth. These crystals contain a toxic insecticidal protein.
- Bt toxin protein exists as inactive protoxins but once an insect ingests the inactive toxin, it is converted into an active form of toxin due to alkaline pH of the gut which solubilises the crystals. .
- The activated toxin binds to the surface of midgut epithelial cells and create pores that cause cell swelling and lysis leading to death of an insect.
- Specific Bt toxin genes were isolated from Bacillus thuringiensis and incorporated into several crop plants.
- Most Bt toxins are insect group specific. Hence, the toxin is coded by a gene named ‘cry’. For example, the proteins encoded by the genes Cry I Ac and Cry II Ab control the cotton bollworms and Cry I Ab controls corn borer.
B) Pest resistant plants are developed by using biotechnology processes :
- A nematode Meloidegyne incognitia infects the roots of tobacco plants which reduces the production of tabaco.
- RNA interference (RNA i) process is used to check by silencing of a specific mRNA due to a complementary RNA molecule. It occurs in all eukaryotic organisms as a method of cellular defense.
- RNA binds and prevents translation of the mRNA (silencing).
- Agrobacterium vectors are used to introduce – specific genes into the host plant. It produces both sense and anti – sense RNA in the host cells.
- These two RNAs are complementary to each other and formed a double stranded RNA (ds RNA) that initiate RNAi and hence silenced the specific mRNA of the nematode.
- The parasite cannot survive in transgenic host, so prevents the plants from pest. The transgenic plant, thus gets itself protected from the parasite.
Write notes on green revolution and gene revolution.
Green revolution :
i) Around 1960s, several countries including India experienced substantial and dramatic increase in agricultural production which was termed as green revolution by William Gaud.
Norman Borlaug is regarded as “Father of Green Revolution”.
ii) Green revolution increased food production by the following ways.
- Use of improved crop varieties
- Use of agro-chemicals (fertilizers and pesticides)
- Use of better management practices
- By land reforms
Gene Revolution :
With the advent of biotechnology, especially the genetic engineering, has increased the food production and decreased the use of chemical fertilizers and pesticides which lead to other type of revolution called Gene revolution.
Gene revolution provided new plants that would to lead to a more environmentally sound agricutural production.
GR plants are useful in many ways. Their
- production of high yeilding and disease resistant varieties.
- made crops more tolerant to abiotic stresses (cold, drought; salt, heat).
- reduced reliance on chemical pesticides (Pest-resistant crops) eg : Bt Cotton.
- helped to reduce past harvest losses.
- increased efficiency of mineral usage by plants. This prevents early exhaustion of fertility of soil.
- enhanced nutritional value of food. Eg : Vitamin A enriched rice.
Long Answer Type Questions
Give an account of bio-technological applications in agriculture and other fields.
Bio-technology application in agriculture : Involves following three options
- Agro-chemical based agriculture
- Organic agriculture
- Genetically engineered crop based agriculture.
Genetically modified organisms (GMO) are plants, animals, bacteria and fungi whose genes have been altered by manipulation.
Genetic modification in organisms lead to following results :
- Crops become more tolerant to abiotic stresses, such as cold, drought, salt, heat, etc.
- Dependence on chemical pesticides reduced i.e., pest resistant crop.
- Post harvest losses reduced.
- Efficiency of mineral usage increased in plants (preventing loss of soil fertility).
- Nutritional value of food enhanced eg: Vitamin A enriched rice.
- Tailor-made plants are created to supply alternative resources to industries, in the form of starches, fuels and pharmaceuticals.
Some of the application of biotechnology in agriculture are the production of pest resistant plants, eg : Bt Cotton, Bt Corn, etc.
Bt. Cotton :
It is created by using some strains of a bacterium, Bacillus thuringiensis (Bt is short form).
- This bacterium produces protein that kill certain insects such as lepidopterans (tobacco budworm, armyworm), coleopterans (beetles) and dipterans (flies, mosquitoes).
- Bt toxin proteins exists as inactive protoxins but once insect ingest the inactive toxin it becomes active and leads to death of an insect.
- Most Bt toxins are insect group specific, hence the toxin is coded by a gene named cry. For example, the proteins encoded by the genes Cry II Ac and Cry I Ab control the cotton bollworms and Cry I Ab controls corn borer.
Pest resistant Plants are developed by using biotechnology processes.
- A nematode Meloidegyne incognitia infects the roots of tobacco plants which reduces the production of tobacco.
- Agro bacterium vectors are used to introduce nematode-specific genes into the host plant. It produces both sense and anti – sense RNA in the host cells.
- These two RNA are complementary to each other and forms a double stranded RNA (ds RNA) that initiate RNAi and hence silenced the specific mRNA of the nematode.
- The parasite cannot survive in transgenic host, so prevents the plants from pest. The transgenic plant thus gets itself protected from the parasite.
Biotechnology and Environment:
Bio remediation :
In the process of using microbes and plants to break down or recycle environmental pollutants.
Utilization of sewage and agrowastes to produce biogas and vermicompost.
Biotechnological application in medicine :
Have made immense impact in the area of health care by enabling the mass production of safe and more effective therapeutic drugs.
Vitamins (A, B12 etc.) and antibiotics (pencillin) are produced at low cost using microorganisms.
Genetically engineered insulin leads to sufficient availability of insulin for the management of adult onset diabetes.
Gene therapy is a collection of methods that allows correction of gene defects diagnosed in a child or embryo. Genes are inserted into a person’s cells or tissue to treat a disease. Molecular diagnosis helps to solve the problem of early diagnosis and treatment of diseases.
i) Using conventional methods of diagnosis (serum and urine analysis) early detection of diseases is not possible.
ii) To overcome this problem, some molecular diagnosis techniques provide early detection of diseases. These are
a) Recombinant DNA technology
b) Polymerase Chain Reaction
c) Enzyme Linked Immuno – Sorbent Assay (ELISA)
Intext Question Answers
Crystals of Bt toxin produced by some bacteria do not kill the liacteria themselves because –
a) bacteria are resistant to the toxin
b) toxin is immature;
c) toxin is inactive;
d) bacteria encloses toxin in a special sac.
Toxin is inactive.
In bacteria the toxin is present in an inactive form, called pro toxin, which gets converted into active form when it enters the body of an insect.
What are transgenic bacteria? Illustrate using any one example.
Transgenic bacteria contain foreign gene that is intentionally introduced into its genome. They are manipulated to express the desirable gene for the production of various commercially important products. An example of transgenic bacteria is E.Coli. In the plasmid of E.coli, the two DNA sequences corresponding to A and B chain of human insulin are inserted, so as to produce the respective human insulin chains. Hence after the insertion of insulin gene into the bacterium, it becomes transgenic and starts producing chains of human insulin. Later on these chains are extracted from E.coli and combined to form human insulin.
Compare and contrast the advantages and disadvantages of production of genetically modified crops.
The production of genetically modified (GM) or transgenic plants have many advantages.
- Most of the GM crops have been developed for pest resistance, which increases the crop productivity and therefore reduces the reliance on chemical pesticides.
- Many varieties of GM food crops have been developed, which have enhanced nutritional quality.
For example : Golden rice is a transgenic variety of rice which is rich in vitamin A.
- These plants prevent the loss of fertility of soil by increasing the efficiency of mineral usage.
- They are highly tolerant to unfavourable abiotic conditions.
- The use of GM crops decreases the post harvesting loss of crops. However there are certain controversies regarding the use of genetically modified crops around the world. The use of these crops can affect the native biodiversity in an area. For example : The use of Bt toxin to decrease the amount of pesticide is posing a threat for beneficial insect pollinators such as honey bee. If the gene expressed for Bt toxin gets expressed in the pollen, then the honey bee might be affected. As a result, the process of pollination by honey bees would be affected. Also genetically modified crops are affecting human health. They supply allergens and certain antibiotic resistance markers in the body. Also they can cause genetic pollution in the wild relatives of the crop plants. Hence it is affecting our natural environment.
What are Cry proteins? Name an organism that produces it. How has man exploited this protein to his benefit?
Cry proteins are encoded by cry genes. These proteins are toxins which are produced by Bacillus thuringiensis bacteria. This bacterium contains these proteins in their inactive form. When the inactive toxin protein is ingested by the insect it gets activated by the alkaline pH of the gut. This results in the lysis of epithelial cell and eventually the death of the insect. Therefore man has exploited this protein to develop certain transgenic crops with insect resistance such as Bt Cotton, Bt Corn, etc.
List the advantages of recombinant insulin.
- Its molecular structure is absolutely identical to that of the natural molecule.
- It helps to have continuous supply of insulin and stabilization of its market price etc.
What is meant by the term bio-pesticide? Name and explain the mode of action of a popular bio-pesticide.
Bio pesticides are the plants which are having resistance to insects.
Example: Bt cotton.
- Bt cotton is created by using some strains of a bacterium, Bacillus thuringiensis (Bt is short form).
- Bt toxin protein exist as inactive protoxins, but once an insect ingets the inactive toxin, it is converted into an active form of toxin due to the alkaline pH of the gut which solubilise the crystals.
- The activated toxin binds to the surface of midgut epithelial cells and creates pores that cause cell swelling and lysis leading to death of an insect.