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Biotechnology Through the Ages Revised June 2010 Ancient Biotechnology Not known when biotechnology began Few records exist besides prehistoric carvings and sketches Most early biotechnology focused on finding food and supporting other basic human needs Useful plants were brought in from the wild and planted near dwellings Food preservation most likely came from unplanned events, such as fire or freezing Domestication of plants and animals played a key part in the development of early biotechnology practices Ancient Biotechnology: Domestication Domestication is the adaptation of organisms so they can be cultured Process of domestication most likely began 11,000 to 12,000 years ago in the Middle East Food supplies were often seasonal, and as such were very low in winter Domesticating plants – such as grains – involved collecting seed and growing crude crops, and understanding the seed had to properly mature before it would be good food Plants needed proper water, light, and nutrients Raising animals in captivity began about the same time as domesticating plants, as people found it was easier to have an animal close by than hunt People learned animals’ needs, how they bred, and how to raise young Cattle and sheep were the first domesticated food animals Domestication resulted in people being able to gather and store foods, leading to farming and food preservation methods still used today Ancient Biotechnology: Food Early humans learned hard lessons about food preservation Some foods rotted, while others could change shape and would still be edible Food stored in a cool cave or heated by a fire did not spoil as quickly Immersing foods in sour liquids prevented food decay Food could be stored in leather bags or clay jars Fermentation occurred if certain microorganisms were present in the food, creating an acid condition which slowed or prevented spoiling Cheese was one of the first products made through biotechnology – strains of bacteria and rennet (an enzyme found in calves’ stomach lining) were added to milk Today, most rennet is genetically engineered, and some cheeses don’t even use it! Certain yeasts are fungi used to make bread rise by producing a gas in the dough Vinegar was formed from fermented juices and extracts from fruit and grains Classic Biotechnology Made widespread use of methods from ancient biotechnology, especially fermentation, but adapted them to industrial production Focuses on short-term food production to meet the demands of an increasing population Classic fermentation advancements occurred in the 1800 and 1900s Yeast enzymes chemically changed compounds into alcohol, which can be converted into acetic acid, or vinegar, which can be used in pickling The use of fermenters, specially designed chambers, allowed better control of the process, so new products such as glycerol, acetone, and citric acid resulted Yeasts helped lead to the modern baking industry Fermentation also led to the development of antibiotics, drugs which could combat bacterial infections Limitations in the use of antibiotics keep disease-causing organisms from developing an immunity to the drug Antibiotics are used in both human and animal medicine Modern Biotechnology Often referred to as genetic engineering, modern biotechnology involves the investigation of genes based on research from the mid-1800s Genetics Genetics is the study of heredity, or how traits are passed from parents to offspring Differences in heredity are known as variability Genes are the basic building blocks of genetics – they carry the genetic code Recombinant DNA Technology Use of biotechnology to produce new life forms by moving genetic material from one organism into another Genetically modified bacteria, biodiesel, human insulin, and some new food varieties came about because of this challenging and controversial process You Might have Heard of… Zacharias Janssen: Dutch eyeglass maker who discovered the principle of the microscope in 1590 Anton Van Leeuwenhoek: Developed the single-lens microscope in the 1670s, which was used to observe tiny organisms Gregor Mendel: Austrian botanist and monk who formulated the basic laws of heredity in the mid-1800s after breeding thousands of peas and discovering some traits were dominant and others recessive Johan Friedrich Miescher: Swiss biologist who isolated the nuclei of white blood cells in 1869, leading to the identification of nucleic acid Walter Sutton: Determined chromosomes carried units of heredity Wilhelm Johannsen: Dutch biologist who created the term “gene” Thomas Hunt Morgan: Contributed to the knowledge of X and Y chromosomes and later won the Nobel Peace Prize for his research Ernst Ruska: German electrical engineer who built the first electron microscope in 1932 You Might have Heard of… Alexander Fleming: Discovered penicillin, the first antibiotic drug used in treating human disease, in 1928 Rosalind Franklin: Set up an x-ray diffraction lab which took photographs of DNA and showed it could have a double helix structure James Watson and Francis Crick: Collaborative researchers who produced the first model of DNA structure in 1953 Norman Borlaug: Helped to develop high-producing wheat varieties and won the Nobel Peace Prize in 1971 for his work Mary Clare King: Determined that 99 percent of human DNA is identical to that of a chimpanzee Ian Wilmut: Cloned Dolly the sheep in 1997 Biotechnology Terms to Note Research: Use of systematic methods to answer questions Basic: Require generating new information to gain understanding Applied: Involves use of knowledge already acquired Field Plot: Small area of land used to test questions or hypothesis to simulate results on a larger scale Development: Creation of new products or methods based on research findings Prototype: A pattern for the production of similar products