Andhra Pradesh BIEAP AP Inter 2nd Year Botany Study Material 12th Lesson Biotechnology and its Applications Textbook Questions and Answers.
AP Inter 2nd Year Botany Study Material 12th Lesson Biotechnology and its Applications
Very Short Answer Questions
Give different types of cry genes and pests which are controlled by the proteins encoded by these genes.
The proteins encoded by the genes cry IAC and cry II Ab control the cotton bollworms, cry IAb controls com borer. [Cry protein is a protein toxin produced by Bacillus thuringiensis that kills insects]
Can a disease be detected before its symptoms appear? Explain the principle involved
Yes. Very low concentration of a bacteria or virus (when the symptoms of the disease are not visible) can be detected by amplification of their nucleic acid through PCR. rDNA technology, Enzyme Linked Immunosorbent Assay are some of the techniques that serve the purpose of early diagnosis.
What is GEAC and what are its objectives?
GEAC stands for Genetic Engineering Approval Committee. 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.
Meloidegyne incognitia. A novel strategy adopted to prevent this infestation is process of RNA interference [RNj/fii]
For which variety of Indian rice, has a patent been filed by a USA company?
Give one example for each of transgenic plants which are suitable for food processing and those with improved nutritional quality.
‘Flavr Savr’ – tomato, Golden Rice from Taipei is rich in vitamin A and prevent blindness.
What is green revolution? Who is regarded as father of green revolution?
Green revolution: Substantial and dramatic increase in agricultural production which was termed as green revolution by William Gaud, the director of United States Agency for International development (USAID). Norman Borlaug is regarded as father of Green Revolution. Dr. M.S. Swaminathan and his team is the success of green revolution in our country.
Short Answer Questions
List out the beneficial aspects of transgenic plants.
Plants with desirable characters created through gene transfer methods are called Transgenic plants. Beneficial aspects are :
a) Transgenic crop plants are efficient because they have many beneficial traits like virus resistance, insect resistance and herbicide resistance.
- Papaya in resistant to papaya ring spot virus
- Bt. cotton is resistant to insects.
- Transgenic tomato plants are resistant to bacterial pathogen pseudomonas.
- Transgenic potato plants are resistant to fungus phytophthora.
b) Transgenic plants which are suitable for food processing are produced with improved nutritional quality.
Eg: i) Transgenic tomato “Flavr Savr” are bruise resistant i.e., suitable for storage and transport due to delayed ripening and offers longer shelf life,
ii) Transgenic Golden Rice Taipei’is rich in vitamin A and prevents blindness.
c) Transgenic plants are used for hybrid seed production.
Eg., : Male sterile plants of Brassica napus are produced. This will eliminate the problem of manual emasculation and reduce the cost of hybrid seed production.
d) Transgenic plants have been shown to express the genes of insulin, interferon, human growth hormones, antibiotics, antibodies etc.
e) Transgenic plants are used as bio-reactors for obtaining, commercially useful products, specialised medicines and antibodies on large scale is called molecular farming.
f) Transgenic plants tolerant to abiotic stresses caused by chemicals, cold, drought, salt, heat etc.,
i) Basmati variety of rice was made resistant against biotic and abiotic stresses.
ii) Round up ready soyabean is herbicide tolerant.
What are some bio-safety issues concerned with genetically modified crops?
- There is fear of transferring allergins or toxins to humans and animals as side effects.
- There is a risk 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 Bt. Cotton
Bt.Cotton : Some strains of Bacillus thuringiensis produce proteins that kill certain insects such as lepidopterans (tobacco budworm armyworm), coleopterans (beetles) and dipterans (flies, mosquitoes). Bacillus thuringiensis forms protein crystals which contain a toxic insecticidal protein. The gene responsible for the production of this toxic protein is introduced genetically into the cotton seeds, protects the plants from Bollworm, a major pest of cotton. The worm feeding on the leaves of Bt Cotton plant becomes lethargic and sleepy thereby causing less damage to the plant! Use of Bt Cotton has led to 3 – 27% increase in cotton yield in countries where it is grown.
The toxin is coded by a gene named ‘cry’. The proteins encoded by the genes cry IAc and cry II Ab control the cotton bollworms and Cry IAb controls com borer.
Give a brief account of pest resistant in plants.
Pest resistant plants: Several nematodes parasitize a wide variety of plants and animals. A nematode. Meloidegyne incognitia infects the roots of tobacco plants and causes a great reduction in yield. To prevent this infestation, process of RNA interference was adopted. Using Agrobacterium vectors, nematode specific genes were introduced into the host plant. The introduction of DNA was such that it produced both sense and anti-sense RNAs in the host cells. These two RNAs formed a double stranded RNA that initiated RNAi and thus silenced the specific mRNA of the nematode. The parasite could not survive in a transgenic host expressing specific interfering RNA. The transgenic plant therefore got itself protected from the parasite.
Crystals of Bt toxin produced by some bacteria do not kill the bacteria 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
c) Toxin is inactive
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. Eg.: 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 human Insulin chains. 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.
- 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. Eg.: Golden rice, rich in vitamin A.
- These plants present 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 pest harvesting loss of crops.
- They can affect the native biodiversity in an area.
- They can cause genetic pollution in the wild relative of crop plants hence it is affecting our natural environment.
- They are affecting human health.
What are Cry proteins? Name an organism that produces it. How has man exploited this protein to his benefit?
It is a protein toxin produced by Bacillus thuningiensis that kills certain insects. Man by using there proteins, controls the insects and are minimising the usage of insecticides.
List out the advantages of recombinant Insulin.
- It is supplied continuously.
- Stabilizes the market price.
- Humulin is absorbed more rapidly.
- Humulin is less expensive.
What is meant by the term Biopesticide? Name and explain the mode of action of a popular biopesticide?
The organism which kills the other pathogenic organisms called Biopesticides. Eg. : Bacillus thuringiensis. It produces inactive crystals but once on insect in guts, it is converted into an active form due to alkaline pH of the gut and cause cell swelling and lysis finally the death of the insect.