Grade 12 Biology Unit 1 PDF

BIOLOGY GRADE 12 UNIT 1 Application of Biology  Application of Biology Biology is the science in charge of studying all living beings. It helps us to understand every living organism, from the smallest bacteria (0.1micro meter) to the blue whales. Blue whales are the lar...

BIOLOGY GRADE 12 UNIT 1 Application of Biology  Application of Biology Biology is the science in charge of studying all living beings. It helps us to understand every living organism, from the smallest bacteria (0.1micro meter) to the blue whales. Blue whales are the largest animals ever to live on our planet - 24 to 33 meters - 90,000 to 136,000 kilograms Thursday, November 21, 2024 2  Biologists often focus on a different subset of living organisms, such as birds, plants, or bacteria, to determine their character. where some diseases pests come from, (infections, animal pathologies) and damage to plants (the entomologist) study of the functions of living organisms (physiologist, Biochemist) the evolution of species (evolutionary biologists) the discovery of new drugs (pharmaceutical scientists) genetic engineering (A genetic engineer) Thursday, November 21, 2024 3  research applications with mother cells (a cytologist) global warming (environmental scientist) helps to understand animals (zoologist) helps to understand plants (Botanists) Microbiologists, Mycologists, Pathologies…etc Then, to broaden your understanding of this further you will look at the more everyday examples of the application of this science in the next topics. Thursday, November 21, 2024 4 1.1. Application in Conservation of natural resources After the successful completion of this section, you will be able to: ✓Define natural resources ✓Identify renewable and non-renewable resources ✓Classify natural resources as renewable and non-renewable ✓Describe the role of conservation in protecting and preserving our natural environment ✓Discuss the role of Biology in the conservation of natural resources Thursday, November 21, 2024 5 Keywords Natural resources: resources supplied by nature the resources that exist (on the planet) independent of human actions, include soil, water, air, plants, animals, and energy. Renewable: Capable of being produced without end. Non-renewable: There is a definite amount available. Once used, it cannot be easily made or replaced. Conservation: the act of preserving, guarding/protecting wise use of natural resources to prevent them from disappearing. Extinict: No longer in existence Thursday, November 21, 2024 6  Natural resources can be classified as Thursday, November 21, 2024 7  Ethiopia has many natural resources, such as, gold, platinum, potash, limestone, natural gas, coal, in addition to lakes, volcanic ocean, and water falls. Thursday, November 21, 2024 8  Timber, many different crop plants, coffee plantations, many different species of animals, plants, and birds, make up rich ecosystems. Plants and animals can reproduce and replenish their populations naturally that is why they are considered as renewable resources Some important renewable resources in Ethiopia: (A) Coffee (B) Walia Ibex Thursday, November 21, 2024 9 (C) Sunlight as a source of energy (D) Ethiopian Bush crow  The main sources of renewable resources Agricultural Products: Crops and livestock regenerate seasonally or annually. Wild food sources are also renewable with management. Solar Energy: Energy from the sun. Wind Energy: Energy from wind. Hydropower: Energy from the movement of water in rivers, streams, or dams. Geothermal Energy: Heat from the Earth’s interior. Tidal Energy: Energy from the movement of tides, a form of hydropower. Wave Energy: Energy from the surface motion/kinetic energy/ of oceans or lakes. Biofuels: Fuels from organic materials, such as ethanol and biodiesel. When managed carefully, they can be used, reused and replaced. Thursday, November 21, 2024 10  Non-renewable resources are natural substances that are not replaced at the same speed as that are used up. They are limited resources. Examples include metals such as gold and iron and fossil fuels such as oil, natural gas, and coal. Thursday, November 21, 2024 11 Thursday, November 21, 2024 12  Conserve the non-renewable natural resources of Ethiopia is economically advantageous to mine metals and fossil fuels, have a negative impact on the earth (i.e. climate change) and that by conserving them instead and using renewable energy sources would be more beneficial to the planet. Non-renewable resources are used carefully Renewable resources should be properly managed Thursday, November 21, 2024 13  Environmental impacts from mining Destruction of natural habitat Oil, fuel and chemicals spills contaminating surrounding soil, rivers and groundwater resources Air pollution from mining processing operations Thursday, November 21, 2024 14  Conservation biology is a mission- oriented science that focuses on how to protect and restore biodiversity, or the diversity of life on Earth. Thursday, November 21, 2024 15  Even renewable resources can be lost if we do not manage them carefully. Eg. What should be done to conserve trees? coppicing and having a continual cycle of planting trees to replace the ones being cut down, bearing in mind that there is a lag time for trees to grow. (usually take 20-30 years to reach full maturity, but the growth rate depends on the species) Coppicing: a widespread and traditional form of woodland management where trees or shrubs are repeatedly cut at the base, creating a coppice stool, and allowed to regrow, in order to provide a sustainable supply of wood. Thursday, November 21, 2024 16  Therefore, biologists takes a position in conserving species and saving them from extinction through the preservation of animals and plants in terms of zoos and seed banks stopping the destruction of their natural habitats so the populations are able to increase. Thursday, November 21, 2024 17 Animals in Zoo Seeds stored at the Millennium Seed Bank Royal Botanic Gardens, Kew 1.2.Food and nutrition security Food security, as defined by the United Nations' Committee on World Food Security, a state - all the people have physical, social, and economic access to sufficient, safe, and nutritious food that meets their food preferences and dietary needs for an active and healthy life at all times. This includes food food being reachable to the presence of enough production within the each person without money to buy sufficient, country, food imports, and discrimination safe, and nutritious food Thursday, November 21, 2024 18 stock stored in to meet one’s dietary government granaries needs.  Nutrition security is a situation whereby individuals have access to sufficient, safe and nutritious foods safe water and adequate sanitation health care services knowledge of household and community practices in child care, food storage and preparation and hygiene. Thursday, November 21, 2024 19  However, food insecurity is often rooted in poverty and has long-term impacts on the potential of families, communities, and countries to develop and prosper. Prolonged undernourishment stunts growth slows cognitive development Increases susceptibility to illness Thursday, November 21, 2024 20  Therefore, Biology plays a key role in producing high-nutrient staple crops and developing new products that can combat malnutrition, and thereby improving food utilization. Bio technologests design the manufacturing processes and machinery used to produce food and drink. This allows products to have consistent flavor, color, and texture to be produced in large quantities. Thursday, November 21, 2024 21 Thursday, November 21, 2024 22 1.3.Creating conscious citizens and ensuring sustainable development Conscious citizen: Person who places value on being fully human while connecting with a higher purpose. A conscious citizen is one Who values human life a and relationship with all living things, one who takes the responsibility for transforming skills into action through ethical decision making ultimately improve life and living on the planet. Thursday, November 21, 2024 23 Biology has a vital role in creating conscious citizen by expanding awareness of the social, global, and environmental conditions. Thank you!!!! 1.3.Creating conscious citizens and ensuring sustainable development Conscious citizen: Person who places value on being fully human while connecting with a higher purpose. A conscious citizen is one Who values human life a and relationship with all living things, one who takes the responsibility for transforming skills into action through ethical decision making ultimately improve life and living on the planet. Thursday, November 21, 2024 1  Biology empowers conscious citizens to assume personal responsibility by engaging in and being committed to initiating positive impact reduce production of wastes, and incorporate recycling, reuse strategies for sustaining a greener earth develop innovative and cost effective bio- based technologies/ biotechnology applications to improve life and living on the planet Thursday, November 21, 2024 2  Biology has a vital role in creating conscious citizen by expanding awareness of the social, global, and environmental conditions. The conscious global citizens (biologists) in Ethiopia involved in sustainable development through protecting, managing and monitoring the existing resources analyzing soil, water and air for chemical pollution finding ways to clean up pollution identifying, recording and monitoring the plants, animals and microbes Thursday, November 21, 2024 3 1.4. Applications In Biotechnology Biotechnology is the application of technologies that involve the use of living organisms, or products from living organisms, for the development of products that benefit humans. Genetically modified organisms (GMOs) received genetic material via recombinant DNA technology. If an organism has received genetic material from a different species, it is called a transgenic organism. A gene from one species that is introduced into another species is called a transgene. Thursday, November 21, 2024 4  Crops can be modified to increase yields and to obtain novel products. Biotechnology can be used in the prevention and mitigation of contamination from industrial, agricultural and municipal wastes. Biotechnology can also be used in the diagnosis and treatment of disease. Thursday, November 21, 2024 5 (I). Application of Biology for food Processing and Production This method involves the increasing of foods productivity using Microorganisms. A technology that shows some promise in increasing world food productivity. Example Single-cell protein (SCP) Single-cell protein (SCP) refers to crude or refined protein of algal, bacterial, mold, or yeast origin that is used either as animal feed or human food. It is produced from waste materials such as molasses from sugar refining, petroleum by-products, agricultural and kitchen wastes. In developed countries, an animal feed called Pruteen is produced by mass culture of the bacterium Methylophilus Thursday, November 21, 2024 6 methylotrophus. Mycoprotein, a product made from the fungus Fusarium venenatum. The filamentous texture of this product makes it a likely candidate for producing meat substitutes for human consumption. Thursday, November 21, 2024 7  Spirulina Health food stores carry bottles of dark green pellets or powder that is a culture of a spiral-shaped cyanobacterium (blue-green algae) called Spirulina. This microbe is harvested from the surface of lakes and ponds, where it grows in great mats. In some parts of Africa, Asia, and Mexico, Spirulina has become a viable alternative to green plants as a primary nutrient source. It can be eaten in its natural form or added to other foods and beverages. Thursday, November 21, 2024 8 Vitamins Vitamins are also produced using biotechnology. Vitamin C was the first vitamin to be produced during a fermentation process by using bacteria. Previously, Vitamin B12 or cyanocobalamin and B2 or Riboflavin were obtained from animal liver extract. But, nowadys the production of vitamin- B12 involved fermentation by propionic bacteria. In nature B2 is found in cereals, vegetables and yeast but the yield of B2 can be enhanced hundred to three hundred fold by using microbes.(bacteria, fungi ) Thursday, November 21, 2024 9 (a). Dairy Products Microorganisms are used in making a wide variety of dairy products. Cultured buttermilk, popular in the developed countries, is made by adding Streptococcus cremoris to pasteurized skim milk and allowing fermentation to occur until the desired consistency, flavor, and acidity are reached. Sour cream is made by adding one of these organisms to cream. Streptococcus lactis, S. diacetylactis and Leuconostoc citrovorum, L. cremoris, or L. dextranicum (with different flavors because of variations in fermentation products). Yogurt is made by adding Streptococcus thermophilus and Thursday, November 21, 2024 10 Lactobacillus bulgaricus to milk.  Fermented milk have been made for centuries in various countries in the globe, especially Africa, Asia, and Eastern European. The products vary in acidity and alcohol content. Acidophilus milk is made by adding Lactobacillus acidophilus to sterile milk. Sterilization prevents uncontrolled fermentation by organisms that might already be present in non -sterilized milk. Bulgarian milk is made by L. bulgaricus; it is similar to buttermilk except that it is more acidic and lacks the flavor imparted by the leuconostocs. Sterile milk : rapid heating of milk to a temperature of at least 135°C, keeping it there for a few seconds, and then quickly cooling it down to ambient temperature. Such treatment results in that all microorganisms present in the raw milk are killed. Thursday, November 21, 2024 11 (b). Fermented Meats Microbes such as Lactobacillus plantarum and Pediococcus cerevisiae add flavor by fermenting meats such as salami, summer sausage, and Lebanon bologna. The heterolactic acid fermentation helps preserve the meat and also gives it a strong flavor. Fungi such as Penicillium and Aspergillus, growing naturally on the surfaces of country hams, help to produce their distinctive flavor. Thursday, November 21, 2024 12 (c). Production of beer, wine, and spirits Beer and wine are made by fermenting sugary juices with the main yeast species used is Saccharomyces cerevisiae) Thursday, November 21, 2024 13  whiskey Thursday, November 21, 2024 14 (d). Bread making Microorganisms accomplish three functions in bread making: 1. leavening the flour-based dough 2. imparting flavor and odor 3. conditioning the dough to make it workable Leavening is achieved primarily through the release of gas to produce a porous and spongy product. Without leavening, bread dough remains dense, flat, and hard. Yeast feeds on the sugar contained with the dough, producing carbon dioxide and alcohol, in a process called fermentation. the most common microbes are various strains of the baker's yeast - Saccharomyces cerevisiae and wild yeasts - heterofermentative lactic acid bacteria, Thursday, November 21, 2024 15  Yeast metabolism requires a source of fermentable sugar such as maltose or glucose. Because the yeast respires aerobically in bread dough, the chief products of maltose fermentation are carbon dioxide and water rather than alcohol (the main product in beer and wine). Other contributions to bread texture come from kneading, which incorporates air into the dough, and from microbial enzymes, which break down flour proteins (gluten) and give the dough elasticity. Thursday, November 21, 2024 16  Besides carbon dioxide production, bread fermentation generates other volatile organic acids and alcohols that impart slight flavors and aromas. These are especially well developed in home-baked bread, which is leavened more slowly than commercial bread. Yeasts and bacteria can also impart unique flavors, depending upon the rye bread culture mixture and baking techniques used. The strong flavor of rye bread, for example, comes in part from starter cultures of lactic acid bacteria such as Lactobacillus plantarum, L. brevis, L. bulgaricus, Leuconostoc mesenteroides, and Streptococcus thermophilus. Sourdough bread gets its unique tang from Lactobacillus sanfrancisc. (created through a natural fermentation process involving suitable bacteria and wild yeasts in the environment (from air, baker's hands) on the grain itself.) Thursday, November 21, 2024 17 Sourdough bread 1.5.Genetic Engineering Genetic engineering is the process of transferring DNA from one organism into another that results in a genetic modification; the production of a transgenic organism. Genetic engineering is being used in the production of pharmaceuticals, gene therapy, and the development of transgenic plants and animals. Thursday, November 21, 2024 18 a. Animal breeding and transgenic animals, and plants and disease, and pest management Animal breeding addresses the genetic value of livestock. Selecting for breeding animals with superior traits in growth rate, egg, meat, milk, or wool production, or with other desirable traits has revolutionized the livestock and plant production throughout the entire world. Animals can also be genetically modified (transgenic animals) for valuable traits. There are many potential applications of transgenic methodology in developing new and improved strains of livestock. Thursday, November 21, 2024 19  Practical applications of transgenic technology in livestock production include enhancing reproductive performance increasing feed utilization and growth rate improving carcass composition (relative amounts of muscle, fat and bone) improving milk production and/or composition modification of hair or fiber increasing disease resistance in animals Thursday, November 21, 2024 20 This is made possible by the fact that the genetic code is universal for all living things. Thursday, November 21, 2024 21 b. Tissue culture Plants can be propagated quickly and in large quantity by tissue culture technique. Tissue culture, a method of biological research in which fragments of tissue from an animal or plant are transferred to an artificial environment in which they can continue to survive and function. The cultured tissue may consist of a single cell, a population of cells, or a whole or part of an organ. Thursday, November 21, 2024 22  Plants produced in large amount using this technique include palm trees, orchids, bananas, and carrots. Therefore, tissue culture is seen as an important biotechnology for developing countries for the production of disease-free high quality rapid production of many uniform plants can be produced in reasonably little Thursday, November 21, 2024 23 Thank you!!!!  1.6. Health and Wellbeings Human drugs insulin for diabetics, are being produced by growth hormone for individuals with pituitary dwarfism, and the fermentation of transgenic bacteria that tissue plasminogen activator for heart attack victims, (helps to have received restore blood flow to brain regions affected by a stroke) the appropriate gene from human, cow, or pig. Animal drugs the growth hormones, bovine or porcine somatotropin, (porcine somatotropin is a daily injectable metabolic modifier for growing pigs while bovine somatotropin increases milk production in dairy cows) 1 Thursday, November 21, 2024.  Production of an Insulin 1. The DNA for 6. The bacterium, insulin is first divides and isolated 3. A restriction enzyme cuts produces copies of the plasmid DNA open, the plasmid. The insulin gene, with and makes human complementary sticky ends insulin using the gene in the plasmid. 7. The insulin is extracted from 4. DNA ligase the bacterial enzyme joins 5. The plasmid culture. together the (now genetically plasmid DNA modified) is 2. A plasmid made of and the inserted back DNA is removed insulin DNA. into the from a bacterial cell bacterium.  a. The Manufacture of Antibiotics When micro-organisms are used for the production of antibiotics, it is not their fermentation products that are wanted, but complex organic compounds, called antibiotics, that they synthesise. Most of the antibiotics we use come from bacteria or fungi that live in the soil. The function of the antibiotics in this situation is not clear. One theory suggests that the chemicals help to suppress competition for limited food resources, but the evidence does not support this theory. One of the most productive sources of antibiotics is Actinomycetes. Thursday, November 21, 2024 3 These are filamentous bacteria that resemble microscopic fungi.  a. The Manufacture of Antibiotics Antibiotics attack bacteria in a variety of ways. Some of them disrupt the production of the cell wall and so prevent the bacteria from reproducing, or even cause them to burst open; some interfere with protein synthesis and thus arrest bacterial growth. Those that stop bacteria from reproducing are said to be bacteriostatic Those that kill the bacteria are bacteriocidal. Thursday, November 21, 2024 4  a. The Manufacture of Antibiotics Animal cells do not have cell walls, and the cell structures involved in protein production are different. Consequently, antibiotics do not damage human cells although they may produce some side-effects such as allergic reactions. The actinomycete Streptomyces produces the antibiotic streptomycin. Thursday, November 21, 2024 5  a. The Manufacture of Antibiotics The best known antibiotic is penicillin, which is produced by the mould fungus Penicillium and was discovered by Sir Alexander Fleming in 1928. Penicillin is still an important antibiotic but it is produced by mutant forms of a different species of Penicillium from that studied by Fleming. The different mutant produce different penicillin. The penicillin types are chemically altered in the laboratory to make them more effective and to 'tailor‘ them for use with different diseases. 'Ampicillin', 'methicillin' and 'oxacillin' Thursday, November 21, 2024 6 A fermenter Used For Producing Penicillin Thursday, November 21, 2024 7  b. Biosensors A rapidly developing area of biotechnology, arousing intense international scientific interest, is that of biosensor production. In this field of bioelectronics, living microorganisms (or their enzymes or organelles) are linked with electrodes, and biological reactions are converted into electrical currents then into a measurable signal by these biosensors An electrode is a solid electric conductor that carries electric current into non-metallic solids, or liquids, or gases, or plasmas, or vacuums Electrodes can carry electrical signals from muscles, brain, heart, skin, or other body parts to recording devices to help diagnose certain conditions. Thursday, November 21, 2024 8 b. Biosensors Biosensors are being developed to measure specific components in beer to monitor pollutants to detect flavor compounds in food to measure the concentration of substances from many different environments Thursday, November 21, 2024 9  b. Biosensors Applications include the detection of glucose, acetic acid, glutamic acid, ethanol, and biochemical oxygen demand In addition, the application of biosensors to measure cephalosporin, nicotinic acid, and several B vitamins has been described. Recently biosensors have been developed using immunochemical- based detection system. These new biosensors will detect pathogens, herbicides, toxins, proteins, and DNA. Thursday, November 21, 2024 10  b. Biosensors One of the most interesting recent developments using these approaches is a handheld aflatoxin detection system for use in monitoring food quality. The unit can detect from 0.1 to 50 ppb of aflatoxins in a 1.0 ml sample in less than 2 min. These include major improvements in the stability and durability of these units, which are being made more portable and sensitive. Thursday, November 21, 2024 11  C). Forensic Science Forensic biologists inspect crime scenes to examine potential sources of evidence using blood, saliva, and hair, and then they analyze the specimens in a laboratory, focusing on DNA analysis. Additionally, fingerprints are also important tools to investigate crime This is because each individual has unique fingerprints that do not change throughout life. Forensic biologists also determine the paternity case of a child. Based on their investigations, forensic biologists write up their findings in technical reports and are called upon to give evidence in court. Thursday, November 21, 2024 12 C). Forensic Science When examining the variability at 5-10 different Variable Number of Tandem Repeat (VNTR) loci, the odds that two random individuals would share the same genetic pattern by chance can be approximately 1 in 10 billion. A similar approach is now routinely used for paternity testing. The gel electrophoresis results of two- suspected paternity tests. Therefore, the suspected person (DNA of suspected 2) is the father of the baby (victim). PCR in forensic application. Thursday, November 21, 2024 13  V). Applications In Biomining As the availability of mineral-rich ores decreases, methods are needed to extract minerals from less concentrated sources. This need the new discipline known as biohydrometallurgy, the use of microbes to extract metals from ores. Copper and other metals originally were thought to be leached from the wastes of ore crushing as a result of an inorganic chemical reaction such as those reactions used to extract metals from ores. It was then discovered that this leaching is due to the action of Thiobacillus ferrooxidans. This chemolithotrophic acidophilic bacterium lives by oxidizing the sulfur that binds Thursday, November 21, 2024 14 copper, zinc, lead, and uranium into their respective sulfide minerals, with a resultant release of the pure metal. V). Applications In Biomining Copper in low-grade ores is often present as copper sulfide. When acidic water is sprayed on such ore, T. ferrooxidans obtains energy as it uses oxygen from the atmosphere to oxidiz the sulfur atoms in sulfide ores to sulfate. The bacterium doesn't use the copper; it merely converts it to a water-soluble form that can be retrieved and used by humans. Other minerals also can be degraded by microbes, T. ferrooxidans releases iron from iron sulfide by the same process. Combinations of T. ferrooxidans and a similar organism, T.thiooxidans, degrade some copper and iron ores more rapidly than either one does alone. Thursday, November 21, 2024 15  V). Applications In Biomining Another combination of organisms, Leptospirillum ferrooxidans and FeS ₂ T. organoparus, degrades pyrite (FeS₂) (iron disulfide mineral) and CuFeS₂ chalcopyrite (CuFeS₂), (copper iron sulfide mineral) although neither organism can degrade the minerals alone. Other bacteria can be used to mine uranium, and bacteria may eventually be used to remove arsenic, lead, zinc, cobalt, and gold. However, of late, fewer mining companies are actually using microbes in their processing. Thursday, November 21, 2024 16  A). Solid Waste Treatment: Composting and Landfill Most of it ends up in landfill sites- huge holes in the ground where refuse is deposited to prevent it being a hazard. The non-biodegradable components (metals, plastics, rubble, etc.) remain there more or less indefinitely; however, over a period of time biodegradable material (food waste, textiles, paper, etc.) undergoes a decomposition process. The rate at which this happens is dependent on the nature of the waste and the conditions of the landfill, but can take several decades. Aerobic processes give way to anaerobic ones and a significant result of the latter is the generation of methane. Modern landfill sites incorporate systems that remove this to prevent it being a Thursday, November 21, 2024 17 fire/explosion hazard, and may put it to good use as a fuel source  A). Solid Waste Treatment: Composting and Landfill Many householders separate organic waste items such as vegetable peelings and grass cuttings and use them to make compost. This practice, apart from providing a useful gardening supplement, also substantially reduces the volume of material that has to be disposed of by other means. Fungi and bacteria, particularly actinomycetes, break down the organic matter to produce CO₂, water and humus, a relatively stable organic end product. Compost is not really a fertiliser, since its nitrogen content is not high, but it nevertheless provides nutrients to a soil and generally helps to improve its condition. Thursday, November 21, 2024 18 B). Wastewater Treatment Wastewater may come from domestic or commercial sources; highly toxic industrial effluents may require pretreatment before entering a water treatment system. The aim of wastewater treatment is the removal of undesirable substances and hazardous microorganisms in order that the water may safely enter a watercourse such as a river or stream. Further purification procedures are required before it can be used as drinking water. Wastewater treatment is fundamental to any developed society, and greatly reduces the incidence of waterborne diseases such as cholera. Thursday, November 21, 2024 19 Sewage is the term used to describe liquid wastes that contain faecal matter (human or animal). B). Wastewater Treatment The effectiveness of the treatment process is judged chiefly by the reduction of the wastewater's biochemical oxygen demand (BOD). This is a measure of the amount of oxygen needed by microorganisms to oxidise its organic content. A high BOD leads to the removal of oxygen from water, a certain indicator of pollution. Thursday, November 21, 2024 20 B). Wastewater Treatment Wastewater treatment usually occurs in stages, Primary treatment is purely physical, and involves the removal of floating objects followed by sedimentation, a process that removes up to one-third of the BOD value. Secondary treatment involves microbial oxidation, leading to a substantial further reduction in BOD. This may take one of two forms, both of which are aerobic, the traditional trickling filter and the more recent activated sludge process In the former, the wastewater is passed slowly over beds of stones or pieces of moulded plastic. These develop a biofilm comprising bacteria, protozoans, fungi and algae, and the resulting treated water has its BOD reduced by some 80- 85%. The main component of this is the bacterium Zoogloea, which secretes slime, forming aggregates called flocs, around which other microorganisms suchThursday, as protozoans November 21, 2024attach.21 Thursday, November 21, 2024 22 B). Wastewater Treatment Some of the water's organic content is not immediately oxidised, but becomes incorporated into the flocs. After a few hours' residence in the tank, the sludge is allowed to settle out, and the treated water passes out of the system. Before being discharged to a watercourse, it is treated with chlorine to remove any pathogenic microorganisms that may remain. The principal operating problem encountered with activated sludge is that of bulking. This is caused by filamentous bacteria such as Sphaerotilus natans; it results in the sludge not settling properly and consequently passing out with the treated water Thursday, November 21, 2024 23  B). Wastewater Treatment Both secondary treatment processes result in some surplus sludge, which undergoes anaerobic digestion, resulting in the production of methane and CO₂. The methane can be used as a fuel to power the plant, and any remaining sludge is dewatered and used as a soil conditioner. Care must be taken in this context, however, that the sludge does not contain toxic heavy metals. Thursday, November 21, 2024 24  C). Bioremediation Bioremediation is the use of living organisms or their products for the detoxification environmental and degradation of pollutants. Today many pollutants are degraded with the help of saprophytic microbes; this process is also known as biodegradation. Genetically engineered metabolically breakdown toxic pollutants into harmless compounds and used to clean up pollutants from the environment. Mercury resistant bacteria process metallic mercury (which damages the nervous system) into a nontoxic compound. During bioremediation via microorganisms, enzymes produced by a microorganism modify a toxic pollutant by transforming its structure called biotransformation. Thursday, November 21, 2024 25  D). Biofuels The need to become independent of fossil fuels is driven by both political and environmental concerns. This has accelerated interest in and use of biofuels – fuel (chiefly ethanol) that is obtained by the fermentation of plant material. While corn is currently the substrate of choice, the use of crop residues could significantly boost biofuel yields. Crop residues are the plant material that is usually left in the field after harvest, and it consists of cellulose and hemicellulose. These polysaccharides are polymers of five different hexoses and pentose: glucose,mannose, galactose, xylose and arabinose. While no microorganism naturally ferments all five sugars, a Saccharomyces cerevisiae strain has been engineered to ferment xylose and an E. coli strain that expresses Zymomonas mobilis genes is able to Thursday, November 21, 2024 26 ferment all these sugars. D). Biofuels Another area of research focuses on degrading the cellulose and hemicellulose to release these monomers. This is commonly done by heating the plant material and treating it with acid, which is both expensive and corrosive. Work to harvest cellulase- and hemicellulase-producing fungi as well as bioprospecting for enzymes from thermoacidophiles are ongoing in an effort to replace the harsh thermochemical approach with a biological treatment. Thursday, November 21, 2024 27  E). Biogas Production Biogas is produced by bacteria and archaeans from organic matter in fermenters. Biogas is a combustible gas produced from the anaerobic breakdown of organic matter such as manure, waste plant matter from crops and household organic waste by the activities of the microorganisms. Depending on the construction of the fermenter, biogas is mostly methane with some carbon dioxide, though other gases may be present. Thursday, November 21, 2024 28 E). Biogas Production Three different communities of anaerobic microbes are required. The first group converts the raw organic waste into a mixture of organic acids, alcohol, hydrogen and carbon dioxide. The second group use the organic acids and alcohol from the first stage to produce acetate, carbon dioxide and hydrogen (These first two communities are Eubacteria) The third/last group are Archaea called methanogens. The methanogens produce methane by one of the following two reactions: CO2 + 4H2 CH4 +H2O (reduction of carbon dioxide to methane) CH3COOH CH4 + CO2 (splitting ethanoic acid to from methane and carbon dioxide Thursday, November 21, 2024 29 E). Biogas Production Advantages of biogas 1. Biogas is a fuel used to cook food, and light lamps. 2. Slurry left after biogas production forms a soil conditioner (manure). 3. much cheaper than Liquefied Petroleum Gas for home use. Thursday, November 21, 2024 30 F) Composting Composting is an aerobic microbial driven process that converts solid organic wastes into a stable, sanitary, humus-like material that has been considerably reduced in bulk and can be safely returned to the environment. To be totally effective, it should only use as substrates readily decomposable solid organic waste. In large-scale operations using largely domestic solid organic wastes, the final product is mostly used for soil improvement, but in more specialised operations using specific organic raw substrates (straw, animal manures, etc.), the final product can become the Thursday, November 21, 2024 31 substrate for the worldwide commercial production of the mushroom Agaricus bisporus. F) Composting Composting has only recently become a serious waste management technology, and both theoretical and practical development of the technology is still in its infancy. The primary aim of a composting operation is to obtain, in a limited time within limited compost, final compost with a desired product quality. Composting is carried out in a packed bed of solid organic particles in which the indigenous microbes will grow and reproduce. Free access to air is an essential requirement. The starting materials are arranged in static piles (windrows), aerated piles or covered tunnels, or in rotating bioreactors (drums or cylinders). Some form of pre-treatment of the waste may be required, such as particle size reduction by shredding or grinding. Thursday, November 21, 2024 32 windrows aerated piles rotating bioreactors Thursday, November 21, 2024 33  C) Composting The basic biological reaction of the composting process is the oxidation of the mixed organic substrates with oxygen to produce carbon dioxide, water and other organic by-products After the composting process is completed, the final product most often needs to be left for variable time periods to stabilize. Thursday, November 21, 2024 34 Thank you!!!!  BIOLOGY GRADE 12 UNIT 1 Application of Biology Vii. Application in Industry A). Enzymes Enzymes can be produced by commercial fermentation using readily available feed stocks such as corn-steep liquor or corn-steep liquor molasses. molasses. Fungi (e.g. Aspergillus) or bacteria (e.g. Bacillus) are two of the most common organisms used to produce the enzymes. organisms are selected because they are non-pathogenic and do not produce antibiotics. Feedstock refers to the raw material that is required for some industrial process Thursday, November 21, 2024 2 A). Enzymes The fermentation process is similar to that described for penicillin. If the enzymes are extracellular then the liquid feedstock is filtered from the organism and the enzyme is extracted. If the enzymes are intracellular, the micro-organisms have to be filtered from the feedstock. They are then crushed and the enzymes extracted with water or other solvents. Thursday, November 21, 2024 3 A). Enzymes Some commercial uses of enzymes are listed below. Proteases: In washing powders for dissolving stains from, e.g. egg, milk and blood; removing hair from animal hides; cheese manufacture; tenderizing meat. Lipases: Flavors enhancer in cheese; in washing powders for removal of fatty stains. Pectinases: Clarification of fruit juices; maximizing juice extraction. (Pectin is a soluble fiber (polysaccharide) found in fruits) Amylases: Production of glucose from starch. (textiles, detergents, food and paper industry, and for the generation of ethanol) Thursday, November 21, 2024 4 B). Biological washing powders The majority of commercial enzyme production involves protein- digesting enzymes (proteases) and fat-digesting enzymes (lipases) for use in the food and textile industries. When combined in washing powders they are effective in removing stains in clothes caused by proteins, e.g. blood, egg and gravy, and fats, e.g. grease. Protein and fat molecules tend to be large and insoluble. When they have been digested the products are small, soluble molecules, which can pass out of the cloth. Biological washing powders save energy because they can be used to wash clothes at lower temperatures, so there is no need to boil water. However, if they are put in water at higher temperatures the enzymes become denatured and they lose their effectiveness. Thursday, November 21, 2024 5 Viii. Applications in Agriculture A). Biopesticides These are defined as biological agents, such as bacteria, fungi, viruses, or their components, which can be used to kill a susceptible insect. There has been a long-term interest in the use of bacteria, fungi, and viruses as bioinsecticides / biopesticides. Thursday, November 21, 2024 6  Bacteria: Bacillus thuringiensis and Bacillus popilliae are the two major bacteria of interest. Bacillus thuringiensis is used on a wide variety of vegetable and field crops, fruits, shade trees, and ornamentals. B. popilliae is used primarily against Japanese beetle larvae. Both bacteria are considered harmless to humans. Pseudomonas fluorescens, which contains the toxin-producing gene from B.thuringiensis, is used on maize to suppress black cutworms. black cutworms Thursday, November 21, 2024 7  Viruses: Three major virus groups that do not appear to replicate in warm-blooded animals are used: They are host specific Nuclear polyhedrosis virus (NPV) Granulosis virus (GV) Cytoplasmic polyhedrosis virus These viruses target These viruses cause a chronic These Insect viruses were insects and are disease and reproduce only in the discovered in the 19th popular as insecticides stomach of insects century, and have been known to cause high for farmers targeting mortality in insect lepidopteran larva populations. Thursday, November 21, 2024 8  Fungi: Over 500 different fungi are associated with insects. Infection and disease occur primarily through the insect cuticle. (insect cuticle: extracellular matrix consists mainly of proteins and the polysaccharide chitin) Four major genera have been used. Beauveria bassiana and Metarhizium anisopliae are used for control of the Colorado potato beetle and the froghopper in sugarcane plantations, respectively. Verticillium lecanii and Entomophthora spp., have been associated with control of aphids in greenhouse and field environments. Thursday, November 21, 2024 9 Colorado potato beetle Froghopper Aphids B). The use of Ti plasmid as a vector Use of tumour-inducing (Ti) plasmid of Agrobacterium tumefaciens to introduce glyphosate resistance into soybean crops. One way to introduce transgenes into plants is to use Agrobacterium tumefaciens. This is a species of bacteria that has a plasmid, called the Ti plasmid, that causes tumours in the plants it infects. Tumour: An abnormal mass of tissue that forms when cells grow and divide more than they should or do not die when they should Agrobacterium tumefaciens a soil bacterium that has the ability to infect plant cells and transfer a defined sequence of their DNA to the plant cell by infection and a causative agent of crown gall disease Thursday, November 21, 2024 10 Glyphosate: is a widely used herbicide that can kill certain weeds and grasses. Glyphosate works by blocking an enzyme essential for plant growth  The glyphosate resistance gene is inserted into the Ti plasmid along with an antibiotic resistance gene. The construct is then re-inserted into an A. tumefaciens bacterium. Plant cells are then exposed to the transgenic bacterium and cultured on a plate containing antibiotic. The only plant cells that grow are those that have taken up the plasmid, the others are killed by antibiotic. Amaranthus palmeri A gene for an enzyme that breaks down glyphosate can be introduced into a plant cell culture. This should lead to a reduced use of herbicides. Thursday, November 21, 2024 11 Thursday, November 21, 2024 12  Another important agricultural development is that of genetically modifed plants protected against attack by insect pests. Maize is protected against the corn borer, which eats the leaves of the plants and then burrows into the stalk, eating its way upwards until the plant cannot support the ear. Cotton is protected against pests such as the boll weevil Insect-resistant tobacco also exists, and is protected against the tobacco bud worm, but as yet it has not been grown commercially. Thursday, November 21, 2024 13  Pest resistant GM crops (primarily cotton and maize), have been genetically modified so they are toxic to certain insects. The most likely detrimental effects on the environment of growing an insect- resistant crop are: The evolution of resistance by the insect pests May damage other species of insects Transfer of the added gene to other species of plant Thursday, November 21, 2024 14 Pest Resistant Crops Pest attack is one of the very common problems in a number of different crops all around the globe, these crops may include fodder crops or other crops for the purpose of getting food. One the example of such crops is BT-Cotton. The genes of Bacillus thuringiensis (Bt), inserted in Pest attack cotton crop in order for development of certain protein in it. The protein (delta-endotoxin) is very toxic to a number of different insects. With this aid of biotechnology, the developed BT- Cotton leads to a less pest attack ultimately leading BT-Cotton 15 to a significant more production. Transgenic Animals Although several recombinant proteins used in medicine are successfully produced in bacteria, some proteins require a eukaryotic animal host for proper processing. For this reason, the desired genes are cloned and expressed in animals, such as sheep, goats, chickens, and mice. Animals that have been modified to express recombinant DNA are called transgenic animals. Several human proteins are expressed in the milk of transgenic sheep and goats, and some are expressed in the eggs of chickens. (Human α-antitrypsin, Human growth hormone;(Goat) , Human protein C; (Pig) Human lactoferrin; (Cow)) Mice have been used extensively for expressing and studying the effects of recombinant genes and mutations. Thursday, November 21, 2024 16 Transgenic Plants Manipulating the DNA of plants (i.e., creating GMOs) has helped to create desirable traits, such as disease and drought resistance herbicide and pesticide resistance better nutritional value produce pharmaceuticals better shelflife Plants that have received recombinant DNA from other species are called transgenic plants. Thursday, November 21, 2024 17  Transgenic plants are closely monitored by government agencies to ensure that they are fit for human consumption and do not endanger other plant and animal. Because foreign genes can spread to other species in the environment, extensive testing is required to ensure ecological stability. Thursday, November 21, 2024 18 Cloning Cloning is a method of producing identical copies of genes, cells, or organisms. The products of cloning are called a clone. A clone is a group of genetically identical organisms or cells produced either by asexual reproduction or artificially by cloning techniques. The main advantage of these techniques is that they can make large numbers of plants or animals, which are exact copies of a parent with desirable characteristics. Thursday, November 21, 2024 19 X. Biological warfare Biological warfare (BW) also known as germ warfare is the use of biological toxins or infectious agents such as bacteria, viruses, and fungi with the intent to kill or injure humans, animals or plants as an act of war. (Biological weapons ) The act of bioterrorism can range from a simple hoax/prank to the actual use of these biological weapons. Biological agents may be used for an isolated assassination or to cause death to thousands. A number of nations have or are seeking to acquire biological warfare agents. If the environment is contaminated, a long-term threat to the population could be created. Thursday, November 21, 2024 20 Thank you!!!!