Biology Presentation for Grade 12 CBSE

1. BIOTECHNOLOGY AND ITS APPLICATION

3. › Biotechnology deals with industrial scale production of
biopharmaceuticals and biologicals using genetically modified
microbes, fungi, plants and animals.
› Applications of biotechnology includes: therapeutics,
diagnostics, genetically modified crops for agriculture, processed
food, bioremediation, waste treatment & energy production
Introduction

4. › To supply best catalyst (microbe/ pure enzyme) in the form of
improved organism with better characteristics
› To create optimal conditions by genetic engineering for a
catalyst to function
› Purification of protein/ organic compound by developing
downstream technologies
Major Research Areas of Biotechnology

5. › Increase in the food production can be achieved by:
1. Agro- chemical based agriculture
2. Organic culture
3. Genetically engineered crop- based agriculture
› Green Revolution- crop production increased by using improved
crop varieties, better crop management practices & use of
agrochemicals (fertilizers & pesticides)
› Food supply was tripled but was not enough for growing population
› Agrochemicals were too expensive for farmers to afford
› Increase in yield with existing varieties are not possible with
conventional breeding
Biotechnological applications in Agriculture

6. › Introduction of genetically modified crops was an alternative to
obtain maximum yield by understanding genetics of the crop
› Some useful aspects of GM plants in agriculture:
1. Improvement in nutritional quality, Eg.- Vitamin ‘A’ enriched rice
2. Better nitrogen fixation
3. Tolerant to abiotic stress (cold, drought, salt, heat)
4. Reduce reliance on chemical pesticides (pest- resistant crops)
5. Reduce post harvest losses
6. Increase efficiency of mineral usage by plants (prevent
exhaustion of fertility of soil)
7. Production of diseased resistant crop
8. Micro propagation for bio- mass energy production

8. Pest Resistant Plants
› Biotechnology in agriculture- Pest resistant plants
› Development of pest resistant plants- reduce the use of pesticide
› One such approach- introduction of Bt toxin to target plant; eg.- Bt
cotton, Bt corn, rice, tomato, potato & soyabean
› Bt toxin- produced by Bacillus thuringiensis due to presence of Bt
toxin gene
› Bt toxin gene- cloned from the bacteria and expressed in plants to
provide resistance to insects (no need of insecticide)- Bio- pesticide

9. › Bacillus thuringiensis- Bt toxin (protein) which kills insects like
lepidopterans (tobacco budworm, armyworm), coleopterans
(beetles) & dipterans (flies, mosquitoes)
› Bt toxin gene expresses itself- protein crystals at particular phase of
bacteria- insecticidal protein
› Bt toxin exists as inactive protoxins & on ingestion of it by insect-
active form of toxin due to alkaline pH of gut- solubilize the crystals
› Activated toxin binds to surface of mid gut epithelial cells & create
pores- swellings & lysis- death of insect
› Bt toxin- isolated from bacteria; coded by gene cry; different types
› Incorporated into crop plant depending on type of crop & target pest
› cryIAc & cryIIAb- cotton bollworms & cryIAb- corn borer
Mechanism of Bt toxin & Bt Cotton

11. Bt (in inactive form)
sprayed on Crops
Eaten by insect
Toxin gets activated by
alkaline pH of insect’s gut
Swelling of gut of insect
Death of insect

12. Pest Resistant plants
› Bt toxin is not toxic to all pest or pest become resistant against Bt
toxin
› Another approach to develop pest resistant crop against nematode
parasite- RNA interference (RNAi)
› Eg. Meloidegyne incognita- roots of tobacco
› Principle of RNAi to develop pest resistance- ‘Silencing translation
of specific mRNA’
› RNAi takes place in all eukaryotic organism as a method of cell
defense
› Silencing of specific mRNA due to complementary dsRNA (a type of
RNA molecule to enhance or inhibit translation of mRNA)- binds to
mRNA & prevent translation
› Source of dsRNA/ complementary RNA- Virus (RNA) or
Transposons- genetic element which replicate via an RNA
intermediate

13. › Vector used- Agrobacterium- genetically engineered to introduce
nematode specific genes (DNA)
› Nematode specific gene- introduced into host plant (transgenic plant)
› DNA introduced will produce both sense & anti- sense RNA in host
› Since sense & anti- sense RNA are complementary to each other-
double stranded RNA (dsRNA)- initiates RNAi
› When nematode infest the plant- introduction of nematode genome
takes place & presence of dsRNA- silence specific mRNA of
nematode- initiation of RNAi
› Parasite will not able to survive in host which express interfering RNA
(RNAi)
› Transgenic plant- resistant & protected from parasite
Method to genetically modify crop through RNAi

14. Meloidegyne incognita

15. Biotechnological applications in Medicine
› Biotechnology in medicines
1. Diagnose & treat different diseases with effective recombinant
therapeutic drugs
2. Protect from dangerous diseases
3. Through gene therapy new & healthy genes can be inserted to
replace damaged cells
4. Targeted action of drug by thorough study of genomics
› Recombinant therapeutics do not induce unwanted immunological
responses as in case of similar products isolated from non- human
source
› 30 recombinant therapeutics- approved for human use & 12 of
these- marketed in India

16. › Deficiency of Insulin causes Diabetes which can be controlled by
taking insulin at regular intervals
› Traditionally when human- insulin were not available, insulin of
animals (slaughtered cattle & pigs)
› Animal insulin- trigger some immune response like allergy and
some reaction due to foreign insulin & will not be effective
› Bacteria were genetically engineered- produce human insulin in
large quantities as bacteria can easily grown in culture medium
Genetically Engineered Insulin

17. › First created 1983, Eli Lilly an American company
› Insulin- hormone to regulate blood sugar level & administered in
patients with Diabetes
› Mature insulin- two short polypeptide chains: chain A & chain B
which are linked by disulphide bridges
› Insulin- synthesized as pro- hormone in all mammals- A peptide,
B peptide & additional C peptide- absent in mature Insulin as it
get removed during maturation
› Using rDNA technology two DNA sequences corresponding chain
A & B of human insulin- introduced into plasmids of E. coli-
produce insulin chains separately
› Chains A & B- extracted & combined by disulphide bonds-
human insulin
Genetically Engineered Insulin

18. Maturation of pro- insulin to Insulin

19. Genetic Engineering of Insulin

20. › Is a corrective therapy to correct or treat hereditary diseases (a
gene defect) diagnosed in a child/ embryo
› Method where genes- inserted into cells & tissues to treat disease
› Principle of Gene Therapy:
Normal gene when get inserted into individual cell or embryo with
gene defect the normal gene will take over the function of and
compensate for the non- functional gene
› First clinical gene therapy- 1990 to 4 year old girl with Adenosine
deaminase (ADA) deficiency
› Initially treated- bone marrow transplantation & by enzyme
replacement therapy
Gene Therapy

21. › ADA deficiency disorder- hereditary disorder caused due to
deletion of gene for adenosine deaminase
› Enzyme Adenosine deaminase- crucial for immune system
function
› In gene therapy lymphocytes from blood of patients are isolated &
grown in culture medium
› Functional ADA cDNA- introduced into lymphocytes through
retroviral vector & returned to patients
› Since lymphocytes have short life span- genetically engineered
lymphocytes are periodically introduced into patients
› But if gene isolate from marrow cells producing ADA introduced
into cells in embryonic stage- permanent cure
Method to treat ADA through Gene therapy

22. Gene therapy

23. › Technique- used to diagnose and monitor disease, detect risk, and
decide which therapies will work best for individual patients
› Treatments of a disease be effective- early diagnosis &
understanding pathophysiology is very important
› Conventional methods of diagnosis (serum & urine analysis)- early
detection of diseases- not possible
› Early diagnosis- possible with advanced molecular diagnostics like
recombinant DNA technology, Polymerase chain reaction (PCR),
Enzyme Linked Immuno- sorbent Assay (ELISA)
› Conventional methods- detect presence of pathogens (bacteria &
virus) when disease is well established & produced disease
symptoms- pathogen high body
Molecular Diagnostics

24. Significance of Molecular Diagnostics:
1. Molecular diagnostics like PCR detects pathogens even at very
low concentration- amplification of nucleic acids of pathogens
2. Detect HIV (Human Immuno Deficiency Virus) in suspected AIDS
patients
3. Detect mutations in genes in suspected cancer patients
4. Detect many genetic disorders
› PCR requires single stranded DNA or RNA tagged with radioactive
molecule to hybridize complementary DNA in clones
› Following hybridization the next step- autoradiography
› Clone with mutation (mutated gene)- not appear in photographic
film (probe will not have complementarity with mutated gene)

26. › ELISA- another molecular diagnostics to detect antigen (foreign
substance/ pathogen)
› Works on principle- antigen- antibody interaction
› ELISA- detects pathogen by presence of antigens (proteins,
glycoproteins, etc.) or by antibodies synthesized against pathogens

27. › May be defined as animals that have their DNA manipulated to
possess and express a foreign gene are known as transgenic
animals
Transgenic Animals

28. 1. Normal physiology and development:
› Transgenic animals are designed to study different aspects of genes,
like how genes are regulated, how they affect normal function of
body & its development.
› For eg.- Study of Insulin like growth factor- involved in growth can be
done by introducing genes from other species that alter the formation
of this factor & study the effect that results, also information is also
obtained about biological role of factor in body
2. Study of disease:
› Transgenic animals- model for human diseases in which
investigations of new treatments for diseases & also gives
understanding how genes contribute to development of disease
› Transgenic animal model- cancer, cystic fibrosis, rheumatoid arthritis
& Alzheimer’s disease
Reasons to produce Transgenic animals

29. 3. Biological Products:
› Products produced by living organism some of which are
medicines- expensive
› Transgenic animals can be created by the introduction of genes
which codes for a particular product- induce organism to produce
desirable product in medium. Eg.-human protein (α-1-antitrypsin)
to treat emphysema
› attempts are being made for treatment of phenylketonuria (PKU)
and cystic fibrosis.
› In 1997, the first transgenic cow, Rosie, produced human
protein-enriched milk (2.4 grams per litre)- the human alpha-
lactalbumin and nutritionally more balanced product for human
babies than natural cow-milk

30. 4. Vaccine Safety:
› For vaccine safety vaccines are first tested on transgenic mice,
developed for use in testing before they are used on humans.
› Transgenic mice are being used to test the safety of the polio
vaccine.
› If successful and found to be reliable, they could replace the use of
monkeys to test the safety of batches of the vaccine.
5. Chemical safety testing
› Transgenic animals- introduced with genes which make them more
sensitive than non- transgenic
› They are then exposed to toxic substances- effect studied
› Toxicity testing in such animals will allow us to obtain results in
less time.

32. › Manipulation of living organisms by the human race requires
certain regulations. Ethical standards are required to evaluate the
morality of all human activities that might help or harm living
organisms.
› Genetic modification of organisms- have unpredictable results
when such organisms are introduced into the ecosystem
› Indian Government has set up organizations such as GEAC
(Genetic Engineering Approval Committee), which will make
decisions regarding the validity of GM research and the safety of
introducing GM-organisms for public services.
› The modification/usage of living organisms for public services (as
food and medicine sources, for example) has also created
problems with patents
Ethical Issues

33. › Use of genetic materials, plants & biological resources by
companies granted with patent has triggered public anger since
they have been identified, developed, & used by farmers & people
of specific country

34. › Over 200,000 varieties of rice- found in India which makes India
richest
› Basmati rice one type of rice with unique aroma & flavor and there
are 27 documented varieties of Basmati- grown in India
› 1997 an American company got patent rights on Basmati rice
through US Patent and Trademark office
› This will allow the company to sell a ‘new’ variety of Basmati, in the
US and abroad.
› This ‘new’ variety of Basmati had actually been derived by
crossing with semi-dwarf varieties and claimed as an invention or a
novelty.
› The patent extends to functional equivalents, implying that other
people selling Basmati rice could be restricted by the patent.

36. › Several attempts have also been made to patent uses, products and
processes based on Indian traditional herbal medicines, e.g., turmeric neem
› We should be vigilant and counter these patent applications, else other
countries/individuals may encash on our rich legacy and we may not be
able to do anything about it.

37. › The patenting of plants, genes, and other biological products that
are indigenous to another country
› Biopiracy- use of bio-resources by multinational companies and
other organizations without proper authorization from the countries
and people concerned without compensatory payment.
› Developed countries patent the knowledge and resources of
underdeveloped countries and enjoy immense profits.
› Industrialized nations are rich financially but poor in biodiversity and
traditional knowledge. In contrast the developing & underdeveloped
world is rich in biodiversity and traditional knowledge related to bio-
resources.
› Traditional knowledge related to bio-resources can be exploited to
develop modern applications and can also be used to save time,
effort and expenditure during their commercialization.
Biopiracy

39. › Realization of the injustice, inadequate compensation and benefit
sharing between developed and developing countries led some
nations to develop laws to prevent such unauthorized exploitation of
bio-resources and traditional knowledge.
› The Indian Parliament has cleared the second amendment of the
Indian Patents Bill, that takes such issues into consideration,
including patent terms emergency provisions and research and
development initiative.