Karnataka 2nd PUC Biology Important Questions Chapter 12 Biotechnology and its Applications
Question 1.
What are the major critical research areas of Biotechnology?
Answer:
Three critical research areas of Biotechnology
- Providing the best catalyst in the form of the improved organism.
- Creating optimal conditions, through engineering for catalyst.
- Downstream processing technology to purify the protein/organic compound. ,
Question 2.
What are genetically modified organisms? Mention their significance.
Answer:
An organism developed by introducing a desired foreign gene is Genetically modified organisms.
Ex: Bt Cotton, Bt Brinjal, Bt Soyabean
Significance of Genetically modified organisms (GMO):
- Made crops tolerant to heat, cold, salt, drought stresses.
- Reduced reliance on chemical pesticides.
- Reduce post-harvest losses.
- Increased efficiency of mineral usage by plants.
- Enhanced nutritional value of food.
- Pest resistant plants.
Question 3.
Mention any two advantages of GMO’s?
or
In which way genetically modified plants are useful?
Answer:
Significance of Genetically modified organisms (GMO):
- Made crops tolerant to heat, cold, salt, drought stresses.
- Reduced reliance on chemical pesticides.
- Reduce post-harvest losses.
- Increased efficiency of mineral usage by plants.
- Enhanced nutritional value of food.
- Pest resistant plants.
Question 4.
What are genetically modified organisms? Name two Bt toxin-producing plants?
Answer:
An organism developed by introducing a desired foreign gene is Genetically modified organisms.
Ex. Bt Cotton, Bt Brinjal, Bt Soyabean.
Question 5.
Which soil bacteria produces Bt toxin?
Answer:
Bt- Bacillus thuringiensis – bacterium
Question 6.
Name the protein produced by Bacillus thuringiensis?
Answer:
Protein produced – Crystal protein
Question 7.
Write a note on Bt toxin? One of the applications of biotechnology is the product on of insect resistant
crop plants just by the statements with reference to Bt cotton?
Answer:
Insecticide crystal protein is produced by Bacillus thuringiensis nontoxic to itself (inactive protoxin), if this protoxin is ingested by insect, it is converted into an active toxin form, due to alkaline pH of the gut, which solubilise’the crystals.
The activated toxin binds to the surface of epithelial cells in midgut and create pores, then cause swelling and lysis and eventually cause death of the insect.Thus cotton plant is protected from bollworm .
[Note: The choice of genes depends upon the crops and targeted pest. Toxins are encoded by cry gene.]
Question 8.
Name any two forms cry gene of Bt cotton.
Answer:
- cry I Ac, cry II Ab, cry I Ab.
- Control of Nematode parasites – Pest resistant plants
Question 9.
Name a nematode which infects tobacco plants and explain how it is controlled? (5M)
Answer:
Ex: Meloidegyne incognitia – infects the roots of tobacco plants, leads to reduction in the yield.
Control by process- RNA interference (RNAi):
- RNA i – In eukaryote’s plays a role of cellular defence involves silencing mRNA, by complementary is RNA , which binds & prevents translation of m RNA of the pathogen.
- Using Agrobacterium as vector, nematode specific genes were introduced of RNA in host.
- Introduction of DNA was such that, it produces both sense and antisense RNA in host cells, which formed ds RNA.
- This dsRNA intiates RNAi, by binding to mRNA and prevents translation of mRNA(silencing) of pathogen. Now plant is protected from the parasite Nematode.
Question 10.
Give an account of genetically engineered Insulin?
Answer:
- 1. Insulin consists of short polypeptide chains * A-chain (21 amino acids) (acid chain)
- B-chain (30amino acids) (Basic chain) which are linked together by disulphide bridges.
- In mammals including humans, insulin is synthsised as a proinsulin, which has a single long chain of amino acid. This proinsulin has an extra chain (connecting chain) which is removed during maturation of proinsulin to insulin.
Using recombinant DNA technology Eli lilly (1983) American company prepared chemically synthesised DNA sequence of A and B chain of insulin separately and introduced into plasmids of E. Coli to produce insulin chains. Purified A and B chains were extracted and combined by creating disulphide bonds to form human insulin ‘Humulin’.
Question 11.
Name the first man made insulin?
Answer:
Humulin.
Question 12.
Define Gene therapy? Give an example. OR Name the disorder to which clinical genetherapy was given first.
Write a note on Gene therapy? How ADA deficiency cured by genetherapy.
Answer:
It is a technique of replacing defective gene by normal function gene to correct congenital defects (embryo/ child). Ex: SCID.
The first human gene therapy trial was tried on August 14(1990)on a 4-year old girl with Adenosine deaminase (ADA) deficiency, which causes genetic disease 1 ’severe combined Immune deficiency” (SCID).
ADA enzyme is crucial for the immune system to function . If deleted or impaired it causes SCID.[T-lym- phocytes (immune cell) from bone marrow which gets originate and get differentiated in Thymus (bilobed structure above the heart in thorax)].
It can be cured by patient lacking functioning of T-lymphocytes and ADA gene. By bone marrow transplanta¬tion or Enzyme replacement theory (i.e. ADA).
Question 13.
Why ADA deficiency treatment recurrent in nature?
Answer:
One disadvantage from these cells, is that, these cells are not immortal have with short life span.Repeated genetically engineered lymphocytes injections has to be given to the patient, to control disease.
Solution: If the ADA gene is isolated and introduced into cell at early embryonic stages it could be a permanent cure.
Question 14.
Explain the Molecular diagnosis techniques.
Answer:
The effective treatment of disease requires, early diagnosis and understanding its pathophysiology. ‘Earlier discuss was diagnosed by serum, and urine analysis, but this was not useful for early detection.
- So, modem techniques like, Recombinant DNA technology ELISA (Enzyme-linked Immuno Sorbant assay) are used.
- Infection of pathogens (Viruses and bacteria) can be early detected by amplification of their nucleic acid by PCR, even when the symptoms of the disease are not yet visible.
- PCR is used to detect HIV in suspected AIDS patients and other genetic disorders.
- ELISA test is based on the principle of antigens or by antibodies produced against pathogen.
Question 15.
What are transgenic animals? Give examples.
Answer:
Animals that have DNA that is manipulated to possess and express an forcing gene.Ex: Transgenic Rabbit, Sheep, cows.
Question 16.
Explain significance of transgenic animals?
Answer:
1. Normal physiology and development: Transgenic animals allow us to study, how genes are regulated, and
their affect on the normal function of the body and its development and, to study biological role of genes in the body. Ex:synthesisof Insulin.
2. Study of disease: They are produced to understanding the role of in the development of diseases like cancer, cystic fibrosis, rheumatoid arthritis etc.
Question 17.
Write a note on biological products in transgenic animals?
Answer:
Biological products: They replace expensive biological products which were used as medicine.
They can be created by introduction of the portion of DNA, which codes for particular protein.
Ex: human protein a-I Antitrypsin is used to treat Emphysema [swelling of alveoli, later destroyed] to treat phenylketonuria [Mental retardants due to autosomal gene mutation], –
- To treat cystic fibrosis [hereditary disease, of exocrine gland thick mucus blockage of pancreatic duct, bronchial respiratory infection],
- Babies (Human) can be given nutritional enriched milk, than natural cow milk.
- In 1997 the first transgenic cow Rosie produced, to have human protein enriched milk [24g/It], [for this several human gene were successfully transferred in cows, expressed in the mammary tissues and produced milk which contained alpha-lactalbumin which in present in human],
- Vaccine Safety testing: Vaccines are either dead or living weakened microorganisms administered to man or animals to stimulate immunity to infection, so they are protected against infections later.
Before they are given, safety of vaccines must be tested, for this Transgenic mice are being used to test vaccine safety Ex: polio vaccine. - Chemical safety testing: Transgenic animals are more sensitive to toxic substances than non transgenic animals. If they are exposed to toxic substances, non transgenic animals, exhibit toxic symptoms but not in transgenic animals. This help us to obtain the results faster.
Question 18.
What is emphysema? Name the recombinant protein to treat it?
Answer:
(a) Emphysema is a chronic lung disease caused by damage to aveoli in smokers.
(b) Recombinant protein is α-I Antitrypsin.
Question 19.
Name the first transgenic cow?
Answer:
Rosie.
Question 20.
Which vaccine was being tested on mice?
Answer:
Polio vaccine.
Question 21.
Expand GEAC?
Answer:
Genetic Engineering Approval Committee.
Question 22.
Define patent? Give examples of patented crops.
Answer:
PATENT: A contract between society and an inventor. It is a set of exclusive rights granted by a govt to inventors and prevents others making selling or importing given inventions.
Public anger towards granted patents for products that are indigenous to a specific country.
Eg: Basmati rice is indigenous to India, but American companies got patent right on this rice variety basically it was a cross between Indian Basmathi and semi-dwarf varieties.
[Ex: Neem, Turmeric],
Question 23.
Write a note on biopiracy?
Explain it with reference to Basmathi rice.
Answer:
Biopiracy is a use of bioresources by multinational companies and other organisation without getting ” authorization from the countries and people concerned without compensatory payments. [It is robbery or theft biological and genetic resources indigenous to a country].
Ex: Basmathi rice is unique for its aroma and flavour and 27 varieties are grown in india .
An American company got patent right and allowed the company to sell a new variety of Basmati in abroad
Basically new variety was derived from India farmers Americans crossed the Indian Basmathi rice with semi dwarf of varieties and claimed as their own invention and other people selling Basmathi is restricted by their patent.
Question 24.
What is biopiracy?
Answer:
Use of bioresources by multinational companies without authorisation.
→ The applications of Biotechnology includes therapeutics, diagnostics, GMO, Bioremediations, waste treatment and energy production.
→ Applications in Agriculture:
There were three options for increased food production. Agrochemicals, organic agriculture and Genetical engineered crop based agriculture. The green revolution succeeded in tripling he food supply but yet not enough to feed the growing population. GM crops are possible solutions to minimize the use of fertilizers and chemicals.
→ Bio Technological Application in Medicine:
The recombinant DNA tech has made a great contribution to medicine and enabled mass production of safe and more efficient drugs. At present (30)drugs are produced, of which (12) are marketed in India.
→ Genetically Engineered Insulin:
Insulin – human protein, produced by Islet of Langerhans of pancreas.
Maintain carbohydrates level in the blood:
Deficiency causes Hyperglycaemia and excess glucose is excreted through urine causing Diabetes mellitus. Patients were previously treated with insulin tablets or injection obtained from pancreas of slaughtered cattle and pigs, since Insulin was from animal source,and caused Allergy in some patients, now the Insulin is produced through Recombinant technology using E, coli.
→ Early Gene Therapy Experiments:
T-lymphocytes were extracted from the bone marrow of (blood) SCID patient:
- They are grown in culture outside the body.
- Functional ADA -adenosine deaminase gene is introduced into these cells with help of retro virus as a vector.
- These engineered cells are injected to bone marrow of patient where cells multiply and produce enough ADA to relieve the disease symptoms.
→ Ethical Issues (Moral Rights):
Genetic engineering – raises questions related to hazardous effects of organisms and, products safeguards to be adapted regarding this.
Ethical issues/standards must be there to evaluate all human activities and the biological significance of organisms when introduced into the Ecosystem.
Their fore Govt, of India, has set up Genetic Engineering Approval Committee (GEAC) of MoEF- to take the decision on validity, the safety of GMO (Genetically Modified Organisms) research and organism for public services.