Revision: Cell Biology and Biotechnology Science and Technology 2 SSC (English Medium) 10th Standard Maharashtra State Board

The branch of biology that deals with the study of the structure, types, organelles, division, and various functions of cells is called cytology.

Special cells present in multicellular organisms that have the ability to give rise to all other types of cells and help in growth and wound healing is called stem cells.

Stem cells are specialised cells that give rise to all other types of cells present in the body of multicellular organisms.

Stem cells obtained from adult tissues such as red bone marrow, adipose connective tissue, blood, and cord blood are called adult stem cells.

The undifferentiated cells present in the early embryo before the 14th day of development that can form all types of body cells are called embryonic stem cells.

The technique of bringing about improvements in living organisms by genetic modifications and hybridization, for the welfare of human beings is known as ‘Biotechnology’.

Seeds produced by recombination of genes from two different crop varieties to obtain improved characteristics, especially in fruits, are called hybrid seeds.

It is a livestock breeding and growing practice in agriculture.

The process of administering a vaccine to stimulate the immune system and provide protection against infectious diseases is called vaccination.

Preparation of antigenic proteins of pathogens (weakened or killed) which on inoculation into a healthy person provides temporary/permanent immunity against a particular disease.

Infection is the entry, development, or multiplication of an infectious agent in the human body or animals.

Antibiotics are metabolic products of microorganisms whose very low concentrations are inhibitory or detrimental to other microbes.

A preparation containing specific antigens that is administered to induce temporary or permanent immunity against a particular disease is called a vaccine.

A vaccine produced in genetically modified plants and consumed orally to generate immunity against specific diseases is called an edible vaccine.

A group of small protein molecules produced in the body or by transgenic organisms and used in the treatment of viral diseases is called interferon.

The technique of treating genetic disorders by correcting defective genes in somatic cells is called gene therapy.

The technique of producing stem cells from cloned embryos for treatment of diseases is called therapeutic cloning.

The process of producing an exact genetic replica of a cell, tissue, organ, or entire organism is called cloning.

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Cloning is the process of producing identical copies of a gene, DNA fragment, cell, or organism.

Gene cloning is a genetic engineering technique in which a single copy of a gene or DNA segment is isolated and multiplied to produce many identical copies.

The production of a complete organism by fusion of a somatic cell nucleus with an enucleated ovum is called reproductive cloning.

The removal, absorption, or destruction of toxic chemicals and harmful pollutants from the environment using microorganisms and plants is called bioremediation.

The process of removing pollutants from soil or water using plants is called phytoremediation.

The technique of identifying an individual by analyzing the unique DNA sequence present in each person, similar to fingerprints, is called DNA fingerprinting.

‘Biofertilizer’ contains living micro-organisms which, when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Thus, biofertilizers are organisms that enrich the nutrient quality of the soil.

Nitrogen (N), Phosphorous (P), and Potassium (K) are the three important nutrients among the various nutrients needed for plant growth. These three are called Principal Nutrients.

The rearing of honey bee to obtain honey and other commercially important products is known as apiculture or bee‑keeping.

Apiculture is the rearing of honey bees for honey. It is called Beekeeping.

Breeding between a superior male of one breed with a superior female of another breed is known as cross-breeding.

• Biotechnology is the use of biological systems, cells, and organisms to develop useful products and services for human welfare.
• The term biotechnology was coined by Karl Ereky (1919).
• Traditional biotechnology involves small-scale processes like fermentation (e.g., curd, cheese, wine), while modern biotechnology is large-scale and based on genetic engineering.
• Modern biotechnology was advanced by recombinant DNA (rDNA) technology developed by Cohen and Boyer (1973).
• It involves techniques like gene modification, PCR, and tissue culture, and integrates fields like molecular biology and genetics.
• Biotechnology has wide applications in agriculture and medicine, such as the production of antibiotics, vaccines, insulin, and the development of high-yield and disease-resistant crops.

• Meaning — Animal husbandry is an agricultural practice of breeding and raising livestock (cows, buffaloes, pigs, sheep, camels, goats, etc.). It is both a science and an art.
• Scope — Includes poultry farming, fish farming, beekeeping, sericulture, and lac culture. Animals provide products like milk, eggs, meat, wool, honey, and silk.
• India's Status — India & China have 70% of the world's livestock but produce only 25% of the world's farm output → need for a professional & scientific approach.
• Farm Management — Starts with selecting high-yielding breeds, proper nutrition, clean environment, health maintenance, veterinary supervision & vaccination.
• Aim — Improve quality & productivity using industrial principles of production, processing and marketing with new technologies.

• Principle: Works on the immune system's memory. A vaccine (weakened/inactivated pathogen or its proteins) stimulates antibody production and generates memory B and T-cells.
• On Re-exposure: Memory cells quickly recognise the pathogen and produce massive antibodies to neutralise it.
• Passive Immunisation: Preformed antibodies/antitoxins are directly injected when quick response is needed (e.g., tetanus, snakebite).
• Types of Vaccines: Protein/sugar from pathogen, dead/inactivated pathogen, toxoid, or attenuated (weakened) pathogen.
• Recombinant DNA Vaccines: Antigenic polypeptides produced in bacteria/yeast for large-scale production (e.g., Hepatitis B vaccine from yeast).

• Gene therapy is the treatment of diseases by replacing, altering, or adding genes to correct genetic defects.
• It is used to treat genetic disorders such as haemophilia, cystic fibrosis, sickle cell anaemia, and thalassemia.
• Genes can be delivered into cells by ex vivo (outside the body), in vivo (inside the body), or using vectors like viruses and liposomes.
• There are two types: germ-line therapy (affects future generations, not used in humans) and somatic cell therapy (affects only the patient and is commonly used).
• Gene therapy has applications in treating genetic diseases, cancer, and improving immune response, but it involves technical and ethical challenges.

• DNA fingerprinting is a technique used to identify individuals based on unique patterns in their DNA, mainly using VNTRs (Variable Number Tandem Repeats), also called minisatellites.
• VNTRs are short repetitive DNA sequences that show high variation among individuals, making each DNA profile unique (except identical twins).
• The technique was developed by Alec Jeffreys and even a very small amount of DNA can be used for analysis.
• The process involves DNA extraction from samples like blood, hair, semen, or tissue, followed by PCR amplification if needed and restriction enzyme digestion.
• DNA fragments are separated using gel electrophoresis, transferred to a membrane by Southern blotting, and hybridised with specific VNTR probes.
• The hybridised DNA is visualized using autoradiography, producing a unique banding pattern for each individual.
• DNA fingerprinting is widely used in forensic science, paternity testing, criminal investigations, identification, genetic diversity studies, and disease diagnosis.

• Green Revolution refers to the collective methods used to obtain maximum agricultural yield from minimum land to overcome food scarcity caused by population explosion.
• Development of high-yielding dwarf varieties of wheat and rice, along with proper use of fertilizers, pesticides, and water management, greatly increased food grain production.
• Dr. Norman Borlaug and Dr. M. S. Swaminathan played key roles in the Green Revolution, supported by research institutes like IARI, New Delhi, and other national agricultural research centers.

• White Revolution aimed at increasing milk production and making dairy a self-sufficient and mainstream industry in India.
• Dr. Verghese Kurien led the cooperative dairy movement from Anand, Gujarat, which strengthened milk processing, distribution, and availability across the country.
• Development of milk processing techniques, quality control, and preservation methods made a wide variety of dairy products available nationwide, increasing preference for local and natural milk varieties.

• Organic farming is an eco-friendly agricultural system that avoids chemical fertilizers and pesticides and maintains natural balance in farming.
• It uses organic wastes, biofertilizers, animal manure, and microbes to supply nutrients and maintain soil fertility.
• Crop rotation, biological pest control, and resistant local varieties are used to manage weeds and diseases naturally.
• Organic farming promotes sustainable agriculture, soil health, biodiversity, and long-term productivity, ensuring safe food for humans and environment.

• Meaning — Artificial rearing of honey bees to obtain honey, wax, pollen, bee venom, propolis & royal jelly. Ancient cottage industry.
• 4 Species in India — Apis dorsata (rock bee), Apis florea (little bee), Apis mellifera (European), Apis indica (Indian). Mellifera & Indica = domesticated species.
• Requirements — Areas with shrubs, orchards & crops. Equipment: hive boxes, smoker, bee veil, gloves, uncapping knife, queen excluder.
• Management — Periodic inspection of cleanliness, queen activity, brood condition & water supply is necessary.
• Importance — Honey = nutritious + medicinal. Bees pollinate sunflowers, mustard, apples, mangoes, and citrus → increases crop productivity.