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KS4 Biology. Biotechnology. What is biotechnology?. Living things use chemical reactions to produce new materials. Biotechnology is the use of these reactions by humans to manufacture useful products. Uses of biotechnology. What products are made using biotechnology?. bread.
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KS4 Biology Biotechnology
What is biotechnology? Living things use chemical reactions to produce new materials. Biotechnology is the use of these reactions by humans to manufacture useful products.
Uses of biotechnology What products are made using biotechnology?
bread cheese and yoghurt beer and wine Biotechnology – an old art Can you think of some products that have been made using biotechnology for thousands of years?
Contents Biotechnology Introducing biotechnology Enzymes Fermentation Other uses of biotechnology Summary activities
carbondioxide + glucose ethanol + C6H12O6(aq) C2H5OH (l) CO2 (g) What is fermentation? Yeast cells contain enzymes that converts sugars (such as glucose and sucrose) into alcohol (ethanol) and carbon dioxide. This reaction is called fermentation. Fermentation usually takes place at 20-30°C. It must take place in anaerobic conditions (without oxygen) otherwise the ethanol would react with oxygen and turn into vinegar.
water bath at 35°C sugar solution and yeast limewater Fermentation in the lab How can fermentation be shown to create carbon dioxide?
A froth of CO2 and yeast during fermentation Uses of fermentation Fermentation has been used for thousands of years in brewing and baking. • Alcoholic drinks such as beer and wine are made by adding yeast to sugary solutions. • Bread rises due to the production of bubbles of carbon dioxide in the fermenting dough.
Grapes convert carbon dioxide to glucose by photosynthesis. Grapes are crushed to release their juice, which contains the glucose. The juice is fermented under anaerobic conditions by the natural yeast on the grape skins. The enzymes in the yeast convert the glucose to alcohol. Fermentation and wine-making
Barley grains are warmed with water to germinate. This produces sugar. Barley is boiled with water to release the sugar. Hops are added for flavour. Yeast is added and enzymes in this convert the sugar to alcohol. Beer is usually filtered and the yeast recycled to make more beer. Fermentation and beer-making
Flour is mixed with water, yeast, salt and sugar to make a dough. The dough is left in a warm environment to allow fermentation. Fermentation produces carbon dioxide gas, which makes the dough rise. The bread is baked, killing the yeast and evaporating the alcohol. Holes are left in the mixture where the CO2 gas expanded. Fermentation and bread-making
Contents Biotechnology Introducing biotechnology Enzymes Fermentation Other uses of biotechnology Summary activities
Pasteurized or sterilized milk is used to kill unwanted bacteria. The milk is mixed with specially-cultured bacteria and kept warm. The enzyme lactase from the bacteria convert milk sugar (lactose) into lactic acid, which gives a sour taste and makes the product semi-solid. Making yoghurt