Afera Biology G-12 Unit 1 PDF

What is biology?  Biology is the study of all living organisms from the smallest bacteria to the biggest blue whales.  Why we study biology? It helps us  To determine where diseases come from and the factor that causes diseases  To control the spread of infectious diseases  To...

What is biology?  Biology is the study of all living organisms from the smallest bacteria to the biggest blue whales.  Why we study biology? It helps us  To determine where diseases come from and the factor that causes diseases  To control the spread of infectious diseases  To know where pests come from  To understand the evolution of living organisms  To discover new drugs and vaccines Application in conservation of natural resources  Conservation is the act of preserving and protecting of natural resources. OR  Conservation is the sustainable and wise use of natural resources to prevent them from extinct.  Nature is the natural, physical, material world.  Natural resources: - are resources (actual or potential) that exist in nature and are useful for human being.  It includes soil, water, air, plants, animals and energy.  Ethiopia has many natural resources like gold, platinum, potash, limestone, natural gas, coal, lakes, volcanic oceans water fall etc… Con’t…  Conservation biology is the scientific study of nature with the aim of protecting biodiversity, their habitats, and ecosystems from excessive rates of extinction.  Natural resources can be classified as: 1. Renewable:-found in unlimited quantity and they can be replaced and reused again and again.  They are mainly living organism and their products that can replace themselves by reproduction and recycle.  Example: - air, solar energy, water, plant. Animal and microorganism.  If renewable resources are not managed carefully , they can be lost. con,’t… 2. Non-renewable: are found in a limited amount(finite) and can’t be replaced as the same speed as that are used up.  E.g. diamond, gold, iron, coal, petroleum, natural gas, oil  They must be used sparingly  renewable energy sources are more beneficial to planet  Coppicing and having a continual cycle of planting trees to replace the one being cut down.  Biologists works to conserving animals and plants from extinction by:  Establishing zoo, national park, seed bank  Reducing habitat destruction and habitat fragmentation  Creating awareness the need for conservation natural resources Why we conserve natural resources?  Because some natural resources can’t be replaced and may run out due to overuse.  To balance the amount of resources that we have and the amount we need. Ethical reason Economical reason Aesthetic value and Prevent O3 depletion etc 1.2. food and nutrition security  Food security is the state in which all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life.  Low food security is reduced quality, variety of diet  Food insecurity is a situation that exists when people lack secure access sufficient amounts of safe and nutritious food for normal growth and active and healthy life  Food insecurity debilitates society by increasing mortality, diseases and disability.  The world food program classifies 3 hunger conditions.  Malnutrition: refers to deficiencies, excesses or imbalances in a person’s intake of energy or nutrient. OR Con’t..  Malnutrition:- lack of food quality (food content) or lack of essential nutrients in the food.  Wasting: it is severe weight loss due to acute malnutrition resulting from starvation. Undernourishment: when individual’s food consumption is insufficient to provide the amount of energy required to maintain a normal, active and healthy life.  Prolonged undernourishment (the sense of insufficient calories) stunts growth, slows cognitive development and increase susceptibility to illness  Nutrition security: all people have consistent and equitable access to healthy, safe, affordable foods essential optimal health and well-being  Under-nutrition is the result of prolonged low levels of food intake and low absorption of food consumed  Undernourishment (chronic hunger) the status of persons, whose food intake regularly provides less than their minimum energy requirements Con’t…  Nutrition security looks at the nutritional value, affordability, accessibility, and safety of foods that promote well-being.  Food secured is ensured only if 1. Enough food is available for all people 2. All individual have the capacity to buy food 3. All people utilize the right kind of food (food quality) 4. There is no barrier to access food  Biology plays role in producing high nutrient staple crops and new products to improve food utilization.  Biotechnologists design manufacturing process to produce large quantity of food and drink with good flavor, color and texture to ensure food security.  Con’t… Chronic food insecurity Transitory food insecurity Is long term or persistent Is short term or temporary Occurs when people are Occurs when there is a unable to meet their sudden drop in the ability to minimum food requirements produce or access enough over sustained period of food to maintain a good time nutritional status Results from periods of Results from short term poverty and inadequate shocks and fluctuation in access to productive food availability and food access, including year to year variations in demotic food production and food prices For me  Food security for a household means access by all members at all times to enough food for an active, healthy life.  The main dimensions (pillars ) of food security 1. Physical availability of food: sufficient food must be produced on a consistent basis 2. Economic access: ability to obtain food, including effects of price 3. Food utilization: food must be prepared and consumed appropriately as well as availability of adequate clean water and sanitation to prevent food borne disease 4. Food stability: availability, access and utilization of food or continuous availability and access to food. FACTORS OF FOOD SECURITY  Global food supply is not even because some produce more food than others.  Both physical and human factors affect food security. 1. Climate 2. Technology 3. Pests and diseases 4. Water stress 5. Conflict 6. Loss of farm land 7. Poverty : when people have less money, they can’t afford food and unable to work  Impact of food insecurity  Famine: people starve  Soil erosion: occur more rapidly in very dry areas  Deforestation, overgrazing and overcultivation: expose soil to wind and water erosion  Rising prices: less food available leads to increase food prices  Social unrest: when food supplies are low people have to fight for their survival  Costs: the price of cooking oil, sugar, flour etc doubled within short period of time Effects of food insecurity War and conflict Climate change Poor nutrition Food wastes Gender inequality Forced migration Terms  Hunger: uncomfortable or painful sensation caused by insufficient food consumption or result of food insecurity.  Overnutrition: too fat for height and age  Wasting: too thin for height  Stunting: too short for age  Good nutrition status or may suffer micronutrient deficiencies 1.3. creating conscious citizens and ensuring sustainable development  Conscious citizen is a person who places value on being fully human while connecting with a higher purpose.  Conscious citizen takes responsibility for transforming skill into action through ethical decision making to improve life and living on the planet.  Global Conscious citizen is one who understand the wider world and their place in it.  They play an active role in their community and work with others to make our planet more peaceful and sustainable.  Con’t…  Global conscious citizen respect any cultural diversity, human right and solve the problem of the world.  Conscious biologists uses the knowledge of biology:  To solve health related problems  To recycle, reuse and reduce the production of wastes  To find out ways to clean up pollution  To ensure sustainable development  To produce sufficient production to overcome food insecurity.  To protect and manage natural resources and  To minimize the impact of chemicals released from industry How do we become a conscious citizen?  A conscious citizen remains alive to his own responsibilities and duties.  The become eager to take any step for state development  A responsible citizen has knowledge about her or his role in community, state and the world.  They play a role to make the world better place to live.  They stand against injustice in social, economic and environmental sectors. Con’t…  According to the world conservation union there are three (3) model for sustainable developments, they are: 1. Economic  Viability of tourism in the area  Viability of companies demand satisfaction 2. Social  Benefit to local society  Employment  Respect for socio-cultural values 3. Environmental  Preserving biodiversity  Rational use of natural resources What is career development?  Career development is the process of managing life, learning and work over through out his/her life.  It helps to set a goal and acquire skill to achieve it.  Career strategy is any behavior, activity or experience designed to help a person meet their goals  There are short and long term career planning strategy  Good career citizen must set SMART goals  Specific  Measurable  Attainable or achievable  Relevant / reliable  Time bounded APPLICATION IN BIOTECHNOLOGY Define Biotechnology ? *Biotechnology: is the use of technology to use (modify) the part of living organisms or their products to make useful products that benefit human. Example: drug, food supplements, enzyme etc) *Genetically modified organisms (GMOs) is an organism that have received genetic material through recombinant DNA technology. *GMO is any living things whose DNA has been changed in a way that would not occur in nature. *If an organism has received genetic material from another species, it is said to be Transgenic organism. *A gene which transferred from one species into another is called a transgene. *Crop plants can be genetically modified to increase their yield, nutritional value and diseases resistant. *Biotechnology can be used in the prevention and mitigation of industrial, agricultural and municipal wastes. *It can be also used in the diagnosis and treatments of diseases. Application of biology in food processing and production Con’t…  Microorganisms can be used to increase food productivity.  Single-cell proteins (SCP):- is produced from waste materials such as molasses from sugar refining, petroleum by-products and agricultural wastes.  SCP is a generic term for crude or refined protein whose origin is yeast, fungi, algae and bacteria which are grown for human and animal consumption.  It is an idea to solve global food scarcity and give relief to the agriculture sector which uses large area for production of protein crops  Con’t  SCP has many advantages, such as  high protein content  contains all the essential amino acids  some microorganisms are highly rich in vitamins  high ratio of surface area to volume  high growth rate  independence of cultivable land and climate  eco-friendly and cost effective  * Con’t… *In developed countries, pruteen is produced by growing Methylophilus methylotrophus bacteria to feed their animals. *Pruteen is the first *Mycoprotein, means ‘protein from fungus’. * It is produced using the fungus Fusarium venenatum, *It contains more proteins and low in fat which can substitute meat for human consumption.. Con’t… Spirulina is a type of blue-green algae (cyanobacteria) that is rich in proteins, vitamin, mineral, carotenoids etc that can be consumed by human and animals. It is harvested from the surface of lakes and ponds which can be eaten in its natural form or added to other foods and beverages. It becomes as a primary nutrient sources in some part of Africa, Asia, and Mexico. Vitamin C was the first vitamin to be produced during a fermentation process by using bacteria. Before Vit. B12 (Cyanocobalamin) &Vit.B2 (Riboflavin) were obtained from animal liver extract but nowadays it is produced by fermentation of propionic bacteria.  Vit.B2 is naturally found in cereals, vegetables and yeast. but it can be enhanced hundred or more fold by using microbes. a. Dairy products: microbes are useful to make dairy product with desired consistency and flavor  Buttermilk is made by adding Streptococcus cremoris to pasteurized skim milk (low fat milk).  Streptococcus lactis, S.diacetylactis, Leuconostoc citrovorum, L.cremoris and L.dextranicum can be used to make buttermilk with different flavor  Sour cream is made by adding one of these microbes to cream.  Yoghurt = Streptococcus thermophilus and Lactobacillus bulgaricus + milk …  Acidophilus milk = Lactobacillus acidophilus + sterile milk  Sterilization prevent uncontrolled fermentation by microorganisms present in milk.  Bulgarian milk is made by L.bulgaricus which is similar to buttermilk but it is more acidic and lacks the flavor imparted by the leuconostocs. b. Fermented meats  Lactobacillus plantarum and Pediococcus cerevisiae add flavor by fermenting meats (like salami, summer sausage, and Lebanon bologna).  The heterolactic acid fermentation helps preserve meat and give tangy flavor.  Penicillium and Aspergillus fungi which grow naturally on the surface of country hams, help to produce their distinctive flavor. * Con’t… c. Production of beer, wine, and spirits *Both beer and wine are non-distilled alcoholic beverages made from partially germinated cereal grains and fruits (grapes) respectively. *Spirits (such as whiskey, gin and rum, brandy, vodka) are distilled alcoholic beverages made from juices. *Distillation is a process of converting a mixture liquid into vapours and then into liquid by condensation process. *The following raw materials are required for beer brewing: Water Malt usually barley malt Hops yeast  Steps in beer brewery process Malting: cereal grain are partially germinated to increase the concentration of starch digesting enzymes that provide the sugar fermentation. Mashing: malted grain is crushed and mixed with hot water to produce mash  In other word, it is a process of converting malt into fermentable sugars  Sweet wort obtained from the mash is transferred to a copper (kettle) for boiling along with dried hops.  Boiling used to stop enzyme action and precipitate proteins.  Hop give beer its bitter flavour, inhibit certain beer spoilage bacteria and maintain foam stability.  Con’t… The dominant types of yeast used to make beer are Saccharomyces cerevisiae (also called ale yeast). This yeast strains is added to proceed the fermentation process in order to produce alcohol, CO2 and other substances (like amyl and isoamyl alcohols, and acetic and butyric acids) After fermentation, the yeast is removed and the beer is filtered, pasteurized and bottled. wine making There are many types of wine such as grapes, peach, pear, dandelion, nuts, blossoms etc. But the most common types of wine is the one which made from fermented grapes juice..  Crushed grapes will undergo a natural fermentation process that produce inconsistent and insufficient amount of ethanol (wine).  In commercial process Juice is treated with SO2 or sometimes pasteurized to destroy any wild yeasts.  Then the right strain of Saccharomyces ellipsoideus are added to keep the fermentation process to produce ethyl alcohol (wine) and other substances.  After fermentation liquid wine is cleared with agents like charcoal to remove particles.  Wine occurs in two distinct types (white and red)  White wine are made from white grapes or can be made from red grapes which its skin is removed.  Spirits. Spiritis a class of alcoholic drinks w/h are unsweetened and produced by distillation of fermented base. The fermented base may be molasses (by-product of sugar industry), fruit juices, cereal extract or sometime a combination of many fermentable substrates. Alcoholic Base material Alcoholic beverage materials Whisky Cereal (barley, rye, corn malt) 40-55% Rum Molasses 40-55% Brandy Fruit juice (grapes) 35-60% Vodka Cereals, potatoes 38-40% Cider Apple juice , other fruits 2-7% Gin Wheat and rye 37-50% Bread making  Bread is still another product of microbial action.  Microbes accomplish three main functions in bread making 1. Leavening the dough 2. Imparting flavor and odor 3. Conditioning the dough to make it workable  Leavening is the production of gases in the baked product to increase volume and to produce shape & texture  baker’s yeast (Saccharomyces cerevisiae)is the common strain of yeast used as a leavening agent in baking bread  Yeast respires aerobically to converts the fermentable sugars (maltose or glucose) present in the dough into CO2 and H2O rather than alcohol Con’t… Carbon dioxide causes the dough to rise and creates the soft texture of bread. Bread texture also come from kneading and from microbial enzymes which break down flour proteins (gluten) Gluten is a protein forms when wheat flour is mixed with water which gives dough its elasticity and texture or shape Any small amount of ethanol that may be produced is evaporated during the baking process. Other microbes like coliform (gas forming), some clostridium species, heterofermentative lactic acid bacteria and wild yeast can be used to make bread. Yeast and mixture can impart unique flavors depending on the culture mixture and baking techniques used. Con’t… E.g. the pungent flavor of rye bread comes from starter cultures of lactic acid bacteria such as: Lactobacillus plantarum L.brevis. L.bulgaricus. Leuconostoc mesenteroides. Streptococcus thermophilus Sourdough bread gets its unique tang flavor from Lactobacillus sanfrancisc. Generally, many other popular foodstuffs are the result of microbial fermentation processes. These include injera, vinegar, soy sauce etc… GENETIC ENGINEERING (GENETIC MODIFICATION).  It is a process of modifying (altering) a genome of an organism by transferring a foreign DNA from one organism into another organism.  Genetic Engineering is the process of altering a DNA structure by either adding or removing genes from it to form a newer gene with desirable characteristics. Genetic engineering is being used in: The production of pharmaceuticals and pharming Gene therapy The development of transgenic plant and The development of transgenic animal.. https://www.youtube.com/watch?v=pUdZDeY EHko  Animal breeding  Is a process of choosing best organisms or organisms with superior traits in breeding.  Animal’s with superior traits means organisms that:  Can lay more egg  Produce sufficient milk  Provide enough meat  Have high growth rate  Can resist diseases  Produce more wool etc  Example: Breeding is important to develop new and improved strain of livestock.  CON’T…  The practical application of transgenic technology in livestock production includes:  Enhancing the prolificacy  Increasing feed utilization  Increasing growth rate  Improving milk production  Modification of hair or fiber  Increasing diseases resistance  Selective breeding can be inbreeding or cross-breeding.  Inbreeding is a type of breeding between related varieties of a species. OR  Inbreeding allows the continuity of (sustain) desirable characteristics. Con’t… But, prolonged inbreeding increases homozygosity and this in turn leads to:  Reduced fertility  Reduced disease resistance and reduce productivity Cross-breeding is a type of breeding between unrelated lines or varieties of the same species. The offspring are called hybrids vigour which usually show phenotypically better than their parent. Hybride vigour is reduced when animals produced by cross- breeding are mated together. Generally cross-breeding: increase heterozygosity Increase productivity and Disease resistance Tissue culture  Is a technique in which a single cell, fragment of tissue, or whole/ part of organ from either plants or animals is transferred to an artificial environment (nutrient media) in which they can continue to survive and function.  Plant tissue culture is widely used to produce clones of a plant by micropropagation method. E.g. palm tree, carrot, banana, orchids etc… Advantage of tissue culture technology In a small area, Sufficient food with desired quality can be produced To rapid produce disease free plants and rapid many uniform plants (monoculture) To regenerate the whole plants from genetically modified plant cell Tissue culture Health and wellbeing's  Genetically modified bacteria produces a range of products, such as: Enzyme for the food industry Thermostable enzymes for washing powders Human growth hormone for dwarfism Bovine or porcine somatotrophin to increase milk yield and muscle development in cattle Insulin for diabetic Tissue plasminogen activator for heart attack victim  Antibiotic Production  Are organic compounds derived from a microorganisms produced synthetically, that destroys or limits the growth of a living organisms.  Antibiotics is produced by both bacteria and fungi that live in the soil but it is not their fermentation by product.  Actinomycetes is the filamentous bacteria that resemble microscopic mold fungi which produce antibiotics.  Streptomycin is an antibiotic produced from actinomycete streptomyces which is used to treat TB, pneumonia, E.coli and other infections caused by certain bacteria  Penicillin is the best known antibiotics which is produced by the mutant species of Penicillium (mold fungi).  It was discovered by Sir Alexander Fleming in 1928.  Con’t…  The penicillin types are chemically altered or modified to make them more effective and to tailor them for use with different diseases. Antibiotic mechanism of action  Inhibit bacterial cell wall (block murein) synthesis  Alter the function and permeability of the cell membrane  Inhibit protein synthesis  Inhibit nucleic acid synthesis  Bacteriostatic:- prevent bacteria from reproducing  Bacteriocidal:- kill bacteria  E.g Ampicillin, Methicillin, Oxacillin are examples of antibiotics. …  Antibiotics do not damage human cells because: Animal do not have cell wall The cell structures involved in protein production are different  Some vaccines are produced by microbial fermentation.  Example vaccine for Bordetella pertussis,Salmonella typhi, Vibrio cholerae, Mycobacterium tuberculosis  Corynebacterium diphtheriae for the synthesis of their toxins, for which toxoids for the DT vaccines are prepared  Primary metabolite is a kind of metabolite that is directly involved in the normal growth, development & reproduction  Secondary metabolites is a derivative primary metabolites  E.g. Phenolic, steroids, antibiotics, pigments  Biosensors  A sensor is a converter that measures a physical quantity & converts into a signal w/h can be read by an instrument  Bioelectronic, living microorganism (e.g their enzymes and organelles) are linked with electrodes, and biological reactions are converted into electrical signal by biosensor.  A biosensor is an analytical device that detects an analyte (e.g. proteins, toxin, vitamin, sugar, antibody, enzymes, DNA, tissue…), that converts a biological responses into an electrical currents or thermal signals.  Biosensors are developed to measure specific components present in beer, to monitor pollutants and to detect flavor compounds in food.  For me  Biosensors are devices or probes that employ a biological element for measuring the concentration of desired substances  Biosensors is an analytical device which uses enzymes, antibody, tissues that converts biological responses into electrical, thermal or optical signals  Biosensor consists two components 1. Sensing element :may be enzymes, antibodies, DNA, tissue or the whole cells 2. Transducer device: is a device that converts a signal in one form energy to another form of energy  Biological elements viruses, bacteria, fungi, protozoa, plant and animal.  It detects the presence and concentrations of a specific substance in any test solution  It is possible to measures and detect the concentration of substances, such as glucose, acetic acid, glutamic acid, ethanol, and biochemical oxygen demand, nicotinic acid, vitamin B etc.  Recently immunochemical biosensors are developed to detect pathogens, herbicides, toxins, proteins and DNA in any test solution.  Biosensor also detects the presence of aflatoxin based on immunoaffinity fluorometric procedure to monitor food quality.  Glucometer biosensor used to detect blood glucose level (for diagnosis of diabetes mellitus)  Application  Disease detection: to detect the presence of different kinds of diseases in human body.  Environmental monitoring: the detection of pesticides and river water contaminates  Food quality monitoring: to monitor the freshness of food and to detect the presence of toxin or pathogen in food.  Drug discovery and evaluation of biological activity of new compounds  Water quality management  Soil quality monitoring Forensic science or DNA fingerprinting  Is a technique used to identify a criminal individual from sample of DNA by looking at unique pattern of their DNA.  Biological samples used for forensics are:- Blood (WBCs), Hair, Saliva, Semen, Skin, Nasal mucus Body tissue cells Any cell that has a nucleus can be used as a sample  DNA fingerprinting is also used to establish paternity  The probability of having two people with the same DNA fingerprint that are not identical twins is very rare.  Every individual has unique fingerprints that don’t change throughout life..  Now day’s, bioinformatics is widely acceptable in the forensic science because it makes easy and reliable to gather biological evidence regarding the crime scene with the help of computational tools.  A DNA sample taken from a crime scene is compared with a DNA sample from a suspect.  If the two DNA profiles are a match, then the evidence came from that suspect.  Conversely, if the two DNA profiles do not match, then the evidence cannot have come from the suspect.  The chance of two random individual that can share the same genetic pattern is approximately 1 in 10 billion.  Fragments are separated on the basis of size by a process called gel electrophoresis  PCR (polymerase chain reaction) is used to copy DNA (gene) several times. Summary  DNA fingerprinting: is used to identify individuals based on their unique DNA sequences.  It helps in:  Forensic investigation ○ To match crime evidence with suspects  Paternity testing ○ To determine biological dad or mom of a child  Organ transplantation ○ To find compatible organ donors for organ recipient  Ancestry tracing ○ Trace the origin and migration of human population Application in biomining 1. Microbiological mining  Biomining can be defined as the extraction of specific minerals from their ores through biological process (usually microorganisms).  Biohydrometallurgy is a new discipline that uses microbes to extract metals from mineral-rich ores.  Bioleaching is the ability of microbes to solubilize metals from insoluble metals.  Copper and other metals were thought to be leached from wastes as a result of an inorganic chemical reactions.  The modern era of booming began with the discovery of Thiobacillus ferrooxidans bacterium.  Thiobacillus ferrooxidans is the most commonly used …  microorganism in bioleaching to extract pure metals.  It is chemo-lithotrophic acidophilic bacterium that lives by oxidizing the sulfur that binds with copper, Zinc, lead, uranium…and releases the pure metals during the process  Copper in low-grade ore is often present as copper sulfide that soaked with weak sulfuric acid wash.  Then the acid reacts with the ores sulfide matrix and encourages the growth of bacterial strain which start to degrade ore and releases minerals or metal in fluid form.  T. ferrooxidans obtains energy by oxidizing the sulfur atoms in sulfide ores (copper sulfide) to sulphate.  The copper can’t be used by the bacterium, rather it will be converted into H2O soluble form that can be retrieved and Con’t…  Thiobacillus ferrooxidans also releases iron from iron sulfide by the same process.  Both T. ferrooxidans and T. thiooxidans degrade some copper and iron ores more rapidly than alone.  The another most common types of microbes which is used for biomining is Leptosprillium ferrooxidans.  Both L. ferrooxidans and T. organoparus in combination can degrades pyrite (FeS2) and chalcopyrite (CuFeS2) but they can’t degrade the mineral alone or separately.  Other bacteria can be used to:  To mine uranium  To remove arsenic, lead, zinc, cobalt , gold etc  Todays fewer mining companies are actually using microbes in their process Solid waste treatment  Waste (also known as rubbish, trash, refuse, junk and garbage) is any unwanted or useless materials.  Solid waste is defined as non-liquid and non soluble materials released from any house or institutions.  It is the process of collecting and treating solid waste for further reuse or proper disposal.  Solid wastes can be divided into two distinct categories 1. Biodegradable are materials that can be easily degraded or broken down naturally by microorganisms (such as bacteria, fungi) For example, food waste, paper, vegetable peels and other kitchen waste, textiles, fruits, tea leaves, wood, etc. Con’t… 2. Non-biodegradable  Non-biodegradable materials are those materials, which cannot be broken down easily, and retain their form for a long period of time.  For example, metals, tin, glass, plastics, rubble etc. Methods of disposal 1. Landfills:  are usually large holes in the ground which used to dispose non-hazardous solid wastes to prevent the damage of human and environment health.  The modern landfills that contains many solid wastes that can generate methane (used as a fuel source ) by anaerobic microbes after a long time. Con’t… 2. Composting:  Biodegradable organic wastes like vegetable peels, egg shells, waste food, leaves, animal wastes etc can be converted into manure by burying them in compost pit  In other word, fungi and actinomycetes bacteria are used to break down the organic waste matter to produce CO2, water and humus  Composite is not really fertilizer because it contains less nitrogen content but composite adds nutrient to improve soil quality.  It also reduces the volume of disposed wastes by other means. 3. Incineration:  Burning of solid organic wastes to convert into gaseous product. Waste water (sewage) treatment  Wastewater can be defined as the flow of used water or liquid wastes discharged from institutions, commercial industries and homes and which is directed to treatment plants.  Sewage is the term used to describe liquid wastes that contain human or animal faecal matter.  The main aim of wastewater treatment is to remove any hazardous (pollutant) substances and pathogens present in the waste water  Then it can be discharged into water bodies or purified further for drinking purpose.  Waste water treatment greatly reduces the water born diseases like cholera Con’t…  The effectiveness of the treatment process is measured by reduction of the wastewater's biochemical oxygen demand (BOD).  BOD is the measure of the oxygen used by microbes to breakdown the organic matter present in the wastewater.  Higher BOD indicates more oxygen is required to degrade the large amounts of degradable materials present in the test water.  Low BOD value means less O2 is being removed from water, so water is generally purer.  The role of microbes in waste treatment is to treat or purify wastewater and make it less harmful to the environment  There are three well-known microbes that keep sewage clean For me  A high BOD refers large quantity of organic waste in the water supply, large number bacteria present to decompose this waste  In this case, the demand for oxygen will be high so the BOD level will be high Stages of waste water treatment  There are three main stages of waste water treatment 1. Primary treatment  Is a purely physical process designed to remove floating objects and materials that will settle (sediment) out.  Raw sewage is first passed through a series of screens to remove large pieces of debris such as sticks, plastic etc  Then the sewage is allowed to settle in a sedimentation tank which further reduces the suspended solid wastes and removes up to one-third of the BOD value. 2. Secondary treatment  Is a biological process which uses mixed microbial population to remove pollutant components from waste water and reduces their concentration prior to disposal.  It also further reduces the BOD value.  The aerobic microbial treatment process can be divided into trickling (percolating) filter and activated sludge A. Trickling filter:-  The wastewater is passed slowly over beds of stones or pieces of moulded plastic that contains microbes (such as fungi, bacteria, protozoans and algae) in the form of biofilms.  These microorganisms break down the waste organic matters and reduces 80-85% of the BOD. B. Activated sludge  The wastewater that have been seeded with a mixed microbial sludge is pumped into aerated treatment tank.  These mixed microbial sludges are used to oxidize the pollutant organic matter in the presence of oxygen Con’t…  One of the main component of the microbial sludge is zoogloea bacterium.  zoogloea bacterium secretes slime that forms flocs (aggregate form) and other microorganism like protozoa attach around it.  Some of the organic content of wastewater is not oxidized immediately rather it becomes part of the flocs.  Then the sludge will be left to sediment in the treatment plant  The water must be treated with chlorine to remove any pathogenic microbes before discharged into water bodies  Bulking which is caused by filamentous bacteria (example Sphaerotilus natans ) is the main problem in activated sludge process.   It causes the sludge not to settle properly and consequently.. passes out with the treated water.  The surplus sludge can be undergo anaerobic digestion to produce CO2 and methane (used to power the plant)  The remaining sludge that does not contain toxic heavy metals can be used as composite 3. Tertiary wastewater treatment  Secondary treatment of wastewaters is effective in removing organic matter from the wastes but it does not remove the inorganic by-products of the microbial activity.  These inorganic products of organic degradation such as ammonia and phosphate can be removed by both chemical and microbiological tertiary treatment process  So if these inorganic products are discharged into water, they cause algal blooming because they are excellent nutrient for algae growth. Bioremediation  Is the use of living organisms or their products for the detoxification and degradation of environmental pollutants  Or bioremediation is the use of living organisms such as bacteria, fungi, algae or plants to remove or reduce toxic pollutants from the environment.  Saprophytic microbes are known by degrading pollutants components.  Genetically engineered bacteria is also used to clean up pollutants from the environments by breaking down the toxic pollutants into less toxic or harmless compounds.  E.g. Mercury that damage nervous system converted into nontoxic compound.  Biotransformation is a process of using microbial enzymes to modify a toxic pollutant by altering or transforming its structure. …  The modified toxic pollutants can be degraded further or not if they are less toxic (e.g toxic heavy metals degraded by microbes into less toxic) Some benefits of bioremediation  It is natural and ecofriendly process  It is cost effective  It remove or immobilize some heavy metals like mercury, lead, arsenic etc by bioaccumulation  It improves the quality of soil, water, and air  It transform a wide of organic pollutant like oil, solvent, pesticide and explosive into harmless like H2O and CO2.  It can provide useful products such as biofuel, enzyme..  Bioremediation can also contributes to the sustainable development goals of reducing poverty, ensuring clean H2O and sanitation, protecting life on land and below water, Biofuels  Biofuels are solid, liquid and gases fuels that have been developed from plant materials.  It is mainly used to describe ethanol fuel which is obtained by the fermentation process of sugar rich plant materials.  Ethanol can be produced from:  Corn resides Ethanol is carbon neutral meaning the  Sugar crops carbon emitted by burning ethanol is also  Crop residues similar with the carbon absorbed by plant.  agricultural and industrial wastes  A plant which is rich in sugar  Crop residues are plant materials which consists of cellulose and hemicellulose left in the field after harvest.  These polysaccharides are a polymers of glucose, galactose, mannose, xylose and arabinose.  There is no microorganisms that ferment these five polymer sugars naturally but genetically engineered Saccharomyces cerevisiae can ferment xylose.  E. coli strain that expresses Zymomonas mobilis genes is another types of microbes that have an ability to ferment all these five polymer sugars effectively.  Though it is expensive and corrosive, it is possible to obtain monomers of sugar from cellulose and hemicellulose by heating the plant materials and treating it with acid in order to produce ethanol.  Today cellulase and hemicellulase producing fungi and enzymes from thermoacidophiles are used to replace the harsh thermochemical approach  Biofuel is used to replace fossil fuels and it is ecofriendly  Using biofuels can reduce greenhouse gas emission  It also used to substitute petrol fuels Biogas production  Biogas is a flammable or combustible mixture of different gases produced by breaking down of organic waste matters anaerobically in fermenter.  The main component of biogas is methane though it also contains CO2, H2O, H2S and other gases  The three main groups of anaerobic microbes involved in biogas production are:  Hydrolytic bacteria (e.g clostridium, Bacteroid & others) are the 1st groups of Eubacteria’s that break down the complex organic molecule like protein, carbohydrate and fat into simpler organic acid, alcohol, hydrogen & CO2 Con’t….  Fermentative bacteria (e.g Acetobacterium, Butyribacterium) are the 2nd groups of Eubacteria’s that ferment the product of the 1st stages such as organic acids and alcohols to produce Acetate, propionic acid, butyric acid, Carbon dioxide and Hydrogen  Methanogenic (e.g Methanobacterium, Methanococcus …) are the 3rd groups of archaea bacteria that produces methane by one of the following two reactions. 1. Reduction of carbon dioxide to methane CO2 + 4H2 CH4 + 2H2O 2. Splitting ethanoic acid to form methane and carbon dioxide CH3COOH CH4 + CO2 Con’t…  The raw materials used to produce biogases are: Sewage from human Manure from animal Farm and garden waste Advantage of biogas Biogas is a fuel used to cook food and light limps Slurry left from biogas production forms a manure Biogas is much cheaper than Liquefied Petroleum Gas for home use  Composite  Is an aerobic microbial driven process that converts solid organic wastes into a stable and humus that used to improve soil  The basic biological reaction of the compositing process is the oxidation of the mixed organic substrates with oxygen to produce CO2, H2O and other organic by-products  The final product of composite can become the substrate for the worldwide commercial production of the mushroom Agaricus bisporus.  Recently, it becomes a good waste management technology  The primary aim of compositing operation is to obtain desired quality product of compost in a limited time. Application in industry Enzymes 1. Enzymes can be made from readily available feed stocks (e.g. corn-steep or molasses) by commercial fermentation.  The two most common microorganisms used to produce enzymes are: 1. Fungi (e.g. Aspergillus) 2. Bacteria (e.g. Bacillus)  These microorganisms are selected because, they are non- pathogenic and do not produce antibiotics.  If the enzymes are extracellular then the liquid feedstock is filtered from the organisms to extract the enzyme.  If the enzymes are intracellular, the microorganism have to be filtered from the feedstock... They are crushed to extract the enzymes with water or other solvents.  Some commercial uses of enzymes are: 1. Proteases  Used in washing powder to remove protein and carbohydrate containing food particles like egg, milk and blood  Used to remove hair from animal hides  Make yoghurt to be creamy and smooth  Used to make meat more tender 2. Lipases  Used in washing powder to remove stains that contain fatty product  Used to enhance flavors and faster cheese making. 3. Pectinases  Used to improve the process of fruit juice extraction  Used for clarification of juices to maximize the production of juice 4. Amylase  Used to hydrolyze starch to sugars prior fermentation or used to produce glucose from starch  Amylases are used to enhance the softness and flexibility of hide (in textile)  Are effective on removing starchy food deposits (in detergent) Biological washing powders  The majority of commercial enzymes are proteases (protein- digesting enzymes ) and lipases (fat-digesting enzymes).  Protease and lipases combined in washing powder became effective to remove stains in clothes caused by proteins (e.g. blood, egg and gravy) and by fats (e.g. grease)  Biological washing powder saves energy because they can be used to wash clothes at lower temperature and no need to boil water  If these enzymes are placed in water at higher temperature, they became denatured and lose their effectiveness. Application in agriculture Biopesticides  Biopesticides are defined as biological agents such as fungi bacteria, viruses or their components which can be used to kill a susceptible insects (bioinsecticides) or pests (biopesticides).. 1. Bacteria  Both Bacillus thuringiensis and Bacillus popilliae are the two major bacteria used as biopesticides because they are harmless to human A. Bacillus thuringiensis is used on vegetables, field crop, fruits, shade tree and ornamentals B. Bacillus popilliae is used primarily against Japanese beetle larvae C. Pseudomonas fluorescens that contains the toxin producing gene from Bacillus thuringiensis is used on maize to suppress black cutworms. 2. Virus  The following three major virus groups that do not replicate in warm-blooded animals are used..  Nuclear polyhedrosis virus (NPV)  Granulosis virus (GV)  Cytoplasmic polyhedrosis virus (CPV) 3. Fungi Over 500 different fungi are associated with insecticide. The following four genera are used to kill insects A. Beauveria bassiana is used for control of the Colorado potato beetle B. Metarhizium anisopliae is used for control of froghopper in sugarcane plantation. C. Both Verticillium lecanii and Entomophthora spp used to control aphids in green house and field environment. The use of tumour-inducing (Ti) plasmid as a vector  Agrobacterium tumenfaciens uses tumour-inducing plasmid to introduce glyphosate resistance gene into soyabean crops. Steps to transfer glyphosate resistance gene  First glyphosate resistance gene is inserted into the Ti plasmid together with antibiotic resistance  Then the Ti plasmid is re-inserted into an Agrobacterium tumenfaciens  Plant cells are exposed to this transgenic bacteria and cultured on a plate containing antibiotics  The plant cells that grow are those that have taken up the plasmid where as the plant that lack the new genes are killed by antibiotics Insect-resistant crops  Genetically modified plants are protected from damage by insect pest. 1. Genetically modified Maize became resistance to the corn borer (attack leaves and stalks as the whole). 2. Genetically engineered cotton became resistance to the boll weevil  The most detrimental effects of growing insect-resistance crops on the environments are:  The evolution of resistance by the insects  Damaging erect on the other species of insects  The transfer of the added gene to other plants species  However, less pesticide is used that reduce the risk of spray carrying to and erecting non-target species of insects in other areas. Pest resistant crops  Pests are mainly insects that damage or destroy crop plants  Pest resistance crops are genetically modified and they are toxic to certain insects.  Cotton, tobacco, corn and other crops have been engineered to express genes encoding for insecticidal (endotoxin) proteins from Bacillus thurigiensis (BT).  A plant that contains a gene from BT produces toxin and show high resistance to caterpillars and insect attack Transgenic Animals  Animals that have been modified to express recombinant DNA technology are called transgenic animals.  Several proteins are produced using genetically engineered bacteria but some recombinant proteins require eukaryotic animal hosts to be produced successfully.  A desired genes that code for proteins are expressed..  in animals such as sheep, goat, chicken and mice.  E.g. Life saving human proteins are produced in the milk of transgenic sheep and goat  Mice have been used to express and study the effect of recombinant genes and mutations. Transgenic plants  Plants can be genetically modified for producing desirable traits such as:  Disease and drought resistance  Herbicide and pesticide resistance  Better nutritional value and shelf life  Plants are also used to produce pharmaceuticals. …  N.B. Genetically modified plants must be monitored by the concern body and ensure they can be used for human food  They also ensure as they will not affect other plant and animal because foreign genes can spread to other species in the environment. Herbicide resistance  Glyphosate is one of the most effective herbicide that kill any green plants including crop plants and weeds but they become harmless as soon as they reach in soil.  A gene that code for an enzyme that breakdown glyphosate can be introduced into a plant cell culture to reduce the use of herbicide chemicals. Cloning  Cloning is a method of producing identical copies of genes, cells or organisms.  Gene cloning is the process of making many copies of a gene (in vivo and in vitro cloning).  Clone is a group of genetically identical organisms produced from one parent.  They can be produced either by asexual reproduction or by artificial (cloning techniques).  Sometimes cloning is used to produce skin or other tissues needed to treat a patient.  The main advantage of cloning techniques is to make large numbers of plants or animals that have exactly the same or copies of a parent with desirable characteristics. Animal cloning  Animals can’t be cloned from small part of their bodies  If animals embryo at early stage is divided into many pieces, each pieces can develop into a separate animal.  However, it is difficult to predict the pieces of embryo that can be develop into animals with desirable traits.  The first successful reproductive cloning of an adult with known characteristics is Dolly sheep.  The first cloned mammal with known characteristics was Dolly (sheep).  Dolly was produced by transferring a diploid nucleus to an enucleated egg (egg without nucleus or cytoplasmic).  The egg cell was stimulated to divide by electric current  When the dividing egg cell reached at blastocyst stage, the …  embryo was implanted into a surrogate mother ewe i.e in vivo cloning  Dolly was born after seven months. Summary  Finn-Dorset ewe was nuclear donor whereas Scottish Blackface was cytoplasmic donor and surrogate sheep uterus donor. Q1. Which sheep is the genetic mother of Dolly?  Gene therapy is treating genetic disease by inserting normal genes to replace defective ones.  Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes Q2. what is in vivo and ex-vivo gene therapy mean? Biological warfare (BW)  Biological warfare and germ warfare is the use of biological toxins (poison) or infectious agents that can be used to kill or incapacitate humans, animals or plants as an act of war by a nation.  Biological agents (or bio-weapons) are living organisms such as bacteria, virus and fungi that reproduce or replicate within their host to cause harm and injure.  Bioterrorism is the intentional use of microbes or toxins as a weapon to cause disease or death for thousands of people.  It can even cause a long term threat to the population and they could spread rapidly around the world too.  Biological weapons disseminate diseases-causing organisms or toxins to harm or kill humans, animals or plants  They can be deadly and contagious.  the international community banned the use of BW.