8. Cell Biology and Biotechnology
Can You Recall?
- What is a cell?
- What is a tissue? What are its functions?
- Which tissue techniques have you studied earlier (e.g., tissue culture)?
- Which processes are involved in tissue culture?
Cytology (Cell Biology)
Cell Biology (Cytology) includes the study of cell structure, organelles, and cell division (mitosis & meiosis), along with many advanced cell processes. It has driven revolutionary changes in human health.
Key Research Centres in India
- National Centre for Cell Science (NCCS), Pune — http://www.nccs.res.in
- inStem, Bengaluru — http://www.instem.res.in
Explore their websites (with your teacher) to see cutting-edge research on cells.
Cell Division (Stages — quick recall)
Stem Cells
Stem cells are special cells in multicellular organisms that can self-renew and differentiate into other cell types. They play a critical role in development and wound healing.
- Early embryo is a mass of similar cells — these are stem cells.
- Later, they differentiate into 220+ specialized human cell types.
- Some adult sites retain stem cells longer: red bone marrow, adipose tissue, and umbilical cord blood.
Preservation
Stem cells (from cord blood, red bone marrow, or blastocyst) are collected aseptically and stored in sterile vials in liquid nitrogen at temperatures \\(-135^{\\circ}\\text{C}\\) to \\(-190^{\\circ}\\text{C}\\).
Types by Source
- Embryonic Stem Cells (pre-differentiation; days 5–7; before ~day 14): can be directed in culture to form required cells/tissues/organs. Property: pleuripotency (pluripotency).
- Adult Stem Cells: from red bone marrow, adipose tissue, blood, and cord blood (post-birth).
Uses of Stem Cells
- Regenerative Therapy
- Cell therapy for diabetes, myocardial infarction, Alzheimer’s, Parkinson’s, etc.
- Producing blood cells for anaemia, thalassemia, leukemia, etc.
- Organ Transplantation — future possibility of growing organs (e.g., kidney, liver) from stem cells.
Organ Transplantation & Donation
Many organs lose function due to ageing, accidents, infections, or disorders. Transplantation can save lives.
Key Points
- Matching factors: blood group, age, diseases/disorders, etc.
- Kidney donation is possible during lifetime (one kidney suffices for excretion). Skin patches can also be donated.
- After death: liver, heart, eyes, etc., can be donated (posthumous donation).
Legal Framework (India)
Transplantation of Human Organs Act, 1994 (amendments: 2009, 2011, 2014) — ensures transparency & prevents exploitation.
Explore
WHO & Organ India websites have detailed resources on brain death, organ & body donation.
Biotechnology — Concept & Benefits
Biotechnology applies cytology, biochemistry, molecular biology and genetic engineering to improve organisms and make useful products (food, medicines, etc.).
Main Areas
- Using abilities of microbes (e.g., milk → yoghurt; molasses → alcohol).
- Using cellular productivity (antibiotics, vaccines from specific cells).
- Using biomolecules (DNA, proteins) for human welfare.
- Gene manipulation for desired traits (plants/animals/products).
- Non-genetic biotech with cells/tissues (e.g., tissue culture, hybrid seeds).
Benefits
- Higher per-hectare yield despite land limits.
- Lower disease-control costs via resistant varieties.
- Fast fruit-setting → more annual yield.
- Stress-resistant crops (temperature, water, soil variability).
Biotechnology in India — Institutions
National Biotechnology Board (1982) → Department of Biotechnology (DBT) (1986). Key institutes:
- National Institute of Immunology
- National Facility for Animal Tissue & Cell Culture
- National Centre for Cell Science
- National Brain Research Centre
- Central Institute of Medicinal & Aromatic Plants
Commercial Applications of Biotechnology
1) Crop Biotechnology
Hybrid Seeds
Genes from two crops recombined to form hybrids — especially fruits.
Genetically Modified (GM) Crops
- Bt Cotton — Bacillus thuringiensis gene produces toxin lethal to bollworm.
- Bt Brinjal — similar concept against brinjal pests.
- Golden Rice — enriched with \\(\\beta\\)-carotene (Vitamin A precursor), ~23× more than normal rice.
- Herbicide-tolerant plants — allow selective weed control.
Biofertilizers
Improve nitrogen fixation & phosphate solubilization:
- Bacteria: Rhizobium, Azotobacter
- Cyanobacteria: Nostoc, Anabaena
- Plant partner: Azolla
Tissue Culture
Genetic improvement and rapid multiplication of elite varieties (traits passed to progeny).
2) Animal Husbandry
Methods: Artificial insemination and embryo transfer → improve quantity & quality of milk, meat, wool; stronger animals for work.
3) Human Health
Diagnosis
- Identify gene links for diseases.
- Early diagnosis (diabetes, heart disease).
- Rapid tests (AIDS, dengue) → early treatment.
Vaccines & Vaccination
- Traditional: killed/attenuated pathogens (some risk).
- Biotech: antigen proteins produced via genes — safer, more thermostable.
- Edible vaccines (in progress): transgenic potatoes against Vibrio cholerae, E. coli (raw consumption to trigger immunity).
Treatment
- Insulin (today via engineered bacteria; earlier collected from animal pancreas as per text).
- Somatotropin (growth), blood clotting factors.
- Interferon (antiviral proteins) from transgenic E. coli.
- Gene therapy (somatic cell) — e.g., PKU via hepatocyte gene correction.
| Protein | Used Against |
|---|---|
| Insulin | Diabetes |
| Somatostatin | Dwarfism |
| Erythropoietin | Anaemia |
| Factor VIII | Haemophilia |
| Interleukin | Cancer (as immunomodulators) |
| Interferon | Viral infections |
Do you know? A transgenic tobacco line developed at IISc helps prevent rinderpest in cattle when leaves are eaten.
4) Cloning
- Reproductive cloning: nucleus of a somatic cell + enucleated ovum → embryo → new organism (no sperm required).
- Therapeutic cloning: derive stem cells from the lab-created embryo to treat diseases.
- Genes can also be cloned (mass copies) for therapy/research.
Ethics
Potential to alter inheritance and traits; human cloning faces strong worldwide opposition.
5) Industrial/White Biotechnology
Cost-effective chemical production — e.g., alcohol from sugar molasses using transgenic yeast.
6) Environment & Biotechnology
Sewage & Solid Waste
Use microbial oxidation before releasing into rivers (to prevent depletion of dissolved oxygen). Solid organic waste → compost (microbe-driven).
Bioremediation / Phytoremediation
- Pseudomonas — cleans hydrocarbons/oil from soil & water.
- Pteris vittata — absorbs arsenic from soil.
- GM Indian mustard — absorbs selenium.
- Sunflower — absorbs uranium & arsenic.
- Deinococcus radiodurans — radiation-resistant; engineered for radioactive cleanup.
- Grasses (alfalfa, clover, rye) — common phytoremediators.
Oil Spillage Cleanup
Use oil-digesting, fast-multiplying bacteria for eco-friendly cleanup. Dr. Ananda Mohan Chakrabarty (often written as Chakravarti in texts) first suggested/applicated such microbial use.
DNA Fingerprinting
Each person’s DNA sequence is unique like fingerprints. Applications: forensics (criminal identification), paternity testing. Indian hub: CDFD, Hyderabad.
Important Stages in Agricultural Development
Green Revolution
To tackle food scarcity from population explosion: dwarf high-yielding wheat & rice, proper fertilizers & pesticides, and water management.
Contributors: Dr. Norman Borlaug (USA), Dr. M. S. Swaminathan (India).
Institutes: IARI (New Delhi), National Citrus Research Institute (Nagpur), National Pomegranate Research Institute (Solapur), IISc, and allied labs.
White Revolution
Dr. Verghese Kurien showed dairy is a mainstream business through co-operatives & biotechnology (quality control, new products, preservation). India moved towards self-sufficiency in milk.
Blue Revolution
Large-scale production of aquatic organisms: fish (rohu, catla), shrimps, lobsters, even aquatic plants. Government’s Nil-Kranti Mission-2016 (NKM-16) provides 50–100% subsidies to encourage pisciculture.
Fertilizers & Insecticides
Fertilizers
- Organic manures improve water-holding/humus; earthworms & fungi mobilize NPK.
- Hydroponics uses liquid chemical fertilizers.
- Overuse of chemicals → soil fertility decline.
Insecticides
- Pesticides increase yield but are poisons (DDT, malathion, chlorpyriphos).
- Enter food web → biomagnification; harm frogs, insectivorous birds, humans.
Organic Farming
Complete ban on chemical fertilizers/pesticides; use local sturdy varieties, maintain natural balance. Rising demand for organic products.
Vermiculture & Oil Cake
Use earthworms to convert organic wastes into rich vermi-compost. Oil cakes (residues after oil extraction) act as good organic fertilizers.
Apiculture (Beekeeping)
Avoid destroying natural hives by smoke/cutting. Use artificial bee boxes to collect honey safely and sustainably.
Cultivation of Medicinal Plants
India’s biodiversity & Ayurveda heritage: cultivate medicinal plants (forests shrinking). Example: Adhatoda vasica (Adulsa) — vasicine in leaves helps cough; Azadirachta indica (Neem) — multiple uses.
Try this
Check a packet of Balghuti, list each medicinal plant & its use.
Fruit Processing
Perishable fruits are preserved/processed into chocolates, juices, jams, jellies, murabba, dried products, and more. Methods: cold storage, drying, salting, airtight packing, evaporation, etc.
Food Biotechnology (Quick Recap)
- Bread — yeast (Saccharomyces cerevisiae) fermentation; \\(CO_2\\) leavening.
- Cheese, Butter, Yoghurt — dairy fermentations.
- Vinegar — acetic acid (~4%) from ethanol via Acetobacter/Gluconobacter.
- Wine/Cider — fruit juice fermentation by yeasts.
- Enzymes — eco-friendly catalysts in many industries.
At a Glance — Flash Revision
Chapter 8 — Exercise: Perfect Solutions
1) Fill in the blanks and complete the statements.
- a. Methods like artificial insemination and embryo transplant are mainly used for animal husbandry.
- b. Stem cell research is the revolutionary event in biotechnology after cloning.
- c. The disease related with the synthesis of insulin is diabetes.
- d. Government of India has encouraged the Blue Revolution (pisciculture) for improving the productivity by launching NKM-16.
2) Match the pairs.
Given
- a. Interferon
- b. Factor (VIII)
- c. Somatostatin
- d. Interleukin
Options
- Diabetes
- Dwarfness
- Viral infection
- Cancer
- Haemophilia
Answer Key
- a–3 (Interferon → Viral infection)
- b–5 (Factor VIII → Haemophilia)
- c–2 (Somatostatin → Dwarfness)
- d–4 (Interleukin → Cancer)
3) Rewrite the wrong statements after corrections.
- a. Incorrect: Changes in genes of the cells are brought about in non-genetic technique.
Correct: Changes in genes of the cells are brought about in genetic techniques (genetic engineering), not in non-genetic techniques. - b. Incorrect: Gene from Bacillus thuringiensis is introduced into soyabean.
Correct: Gene from Bacillus thuringiensis is introduced into cotton (Bt cotton) and brinjal (Bt brinjal) to control specific pests.
4) Short notes.
a) Biotechnology: Professional uses
- Agriculture: Hybrid seeds, GM crops (Bt cotton, Golden rice), biofertilizers, tissue culture for rapid multiplication.
- Healthcare: Vaccines (safer antigen-based), diagnostics (early tests), therapeutics (insulin, clotting factors, interferon), gene therapy.
- Industry (White biotech): Enzymes as eco-friendly catalysts; fermentation products (alcohols, acids).
- Environment: Bioremediation (oil spills, heavy metals), wastewater treatment, biosensors.
- Animal Husbandry: Artificial insemination, embryo transfer to improve yield and quality.
b) Importance of medicinal plants
- Backbone of Ayurveda and traditional healthcare; provide bioactive compounds (e.g., vasicine in Adulsa, neem actives).
- Support primary healthcare, nutraceuticals, and pharmaceutical leads.
- Encourage biodiversity conservation and sustainable rural livelihoods.
- Due to shrinking forests, cultivation ensures steady, quality supply and reduces pressure on wild stocks.
5) Answer the following in your own words.
a) Biotech products used in daily life
Bread, curd/yoghurt, cheese, vinegar, fermented beverages, probiotics; vaccines & antibiotics; bio-fertilizer–grown foods; biogas; enzyme-based detergents.
b) Precautions during spraying pesticides
- Wear PPE (mask, gloves, goggles); avoid windy hours; follow label dose & dilution.
- Keep away from water sources; protect bees and natural enemies; don’t mix incompatible chemicals.
- Keep children/pregnant women away; wash thoroughly after use; dispose containers safely.
- Prefer IPM/biopesticides; never overuse.
c) Why some human organs are most valuable
Vital for life (heart, liver, kidneys, cornea), scarce donors, limited regeneration capacity; timely transplantation can save or transform lives.
d) Importance of fruit processing
Preserves perishable produce, reduces waste, ensures year-round availability, adds value & nutrition, boosts farmer income, jobs, and exports.
e) Meaning of vaccination
Administration of an antigen (killed/attenuated pathogen or antigenic protein) to stimulate immunity and provide protection. Biotech vaccines are safer & more stable; edible vaccines are under development.
6) Complete the chart — Merits of Biotechnology.
7) Write the correct answer in blank circles — Uses of stem cells.
8) Identify & complete the correlations.
- Insulin : Diabetes :: Interleukin : Cancer
- Interferon : Viral infection :: Erythropoietin : Anaemia
- Somatostatin : Dwarfness :: Factor VIII : Haemophilia
- White revolution : Dairy :: Blue revolution : Pisciculture (Fisheries)
9) Comparative note — Usefulness vs Harmfulness of Biotechnology.
| Usefulness | Harmfulness / Concerns |
|---|---|
| Boosts crop yield, nutrition (e.g., Golden Rice); pest/disease resistance; stress-tolerant crops. | Possible ecological impacts (gene flow to wild relatives), biodiversity concerns. |
| Medical advances: safer vaccines, affordable insulin/clotting factors, rapid diagnostics, gene therapy. | Ethical issues (e.g., cloning), privacy concerns (genetic data), equitable access. |
| Bioremediation, clean industrial enzymes, reduced pollution. | Unintended health effects/allergenicity (needs stringent testing); antibiotic resistance risks. |
| Improved livestock via AI/ET; better food security and livelihoods. | Seed/tech dependence; IP and farmer sovereignty issues. |
Balanced approach: strong biosafety regulations, rigorous testing, transparency, and ethical governance help maximize benefits while minimizing risks.