Republic Polytechnic AY 2023 Sem 2 A223 L01 6P PDF

OFFICIAL (CLOSED) \ NON-SENSITIVE Problem Statement L01: Something’s Brewing Activity Owners: Neeyor Bose (Dr) Ventris M. D’souza (Dr) Inputs by: Terence Chong (Dr) Module Chair: Heng Kiang Soon (Dr) Approved by: Serene Ch...

OFFICIAL (CLOSED) \ NON-SENSITIVE Problem Statement L01: Something’s Brewing Activity Owners: Neeyor Bose (Dr) Ventris M. D’souza (Dr) Inputs by: Terence Chong (Dr) Module Chair: Heng Kiang Soon (Dr) Approved by: Serene Choo (Dr) 1  OFFICIAL (CLOSED) \ NON-SENSITIVE Why do yeast convert malt and water to beer? Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What do you recognize? Yeast cells are able to convert malt and water into beer (alcohol) Malt contains a large store of carbohydrates, mainly starch, which is a polysaccharide Biochemical processes are involved in the conversion of malt (substrate) into beer (product) Certain conditions are necessary for this conversion to take place 3 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE An approach What is beer? How is yeast involved in beer making? What are the central biomolecules in beer-making? How do yeast cells get energy from glucose? How much energy can be produced by glycolysis? How is the energy produced by glycolysis stored? Why does glucose breakdown involve so many steps? What are the conditions required for ethanol production? Does fermentation always produce ethanol? What are some industrial applications of fermentation? Why do cells do fermentation? 4 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What is beer? Fermented product of grains and cereals such as rice, barley, sorghum etc. Contains alcohol and froth as a result of dissolved carbon dioxide 5  OFFICIAL (CLOSED) \ NON-SENSITIVE How is yeast involved in beer making? Free living unicellular organism (eukaryote) Main source of energy: breakdown of sugars (glucose) Can survive in aerobic and anaerobic conditions 6 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What are the central biomolecules in beer- making? Malting process Starch (polysaccharide) Glucose (monosaccharide) + Maltose (disaccharide) 7 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE How do yeast cells get energy from glucose? The pathway starts with the 6 Carbon biochemical process called molecule Glycolysis (catabolic reaction): Glycolysis involves breaking down of glucose (6-carbon molecule to Pyruvate (3- carbon molecule) This pathway is a linear as it started with a substrate (glucose) and ended with a product (pyruvate) Via glycolysis, living organisms extract energy 3 Carbon from glucose Pyruvate molecule 8 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE How much energy are produced by glycolysis? Stage 1 Energy input stage: 2 molecules of ATP are used up (-2) Energy generation stage: Stage 2 4 molecules of ATP and 2 molecules of NADH are generated (+4) Total ATP generated = (-2) + (+4) = (+2) 2 NADH molecules can be converted to energy by other biochemical pathways 9  How is the energy, produced via glycolysis, OFFICIAL (CLOSED) \ NON-SENSITIVE stored? All living cells rely on one source of energy to do everything from building molecules to flexing muscles – ATP (adenosine triphosphate) Breaking down ATP releases energy, and cells constantly replenishing their ATP levels by adding on a spare phosphate onto ADP (adenosine diphosphate) The energy from that comes from food we eat (in animals) or make (in plants) 10 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE Why does glucose breakdown involve so many steps? Breakdown that is very fast (burning, explosions, lightning) releases a lot of energy Can be very destructive Energy cannot be utilised effectively Energy lost as heat or light Slow release of energy (battery, car engine) allows for control Not destructive Energy can be used effectively or stored when not needed More efficient. No loss of energy 11 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What are the conditions required for ethanol production? Yeast cells produce ethanol when oxygen levels are low (anaerobic conditions) 12 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE Conditions required for ethanol fermentation Glucose is first converted to pyruvate (by glycolysis) Each pyruvate molecule is converted to one ethanol NAD+ is an important by- product of fermentation CO2 is also released (froth) Enzymes involved are pyruvate decarboxylase and alcohol dehydrogenase 13 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE Does fermentation always produce ethanol? Certain cells produce other compounds under anaerobic conditions Muscle cells produce lactic acid/lactate leading to muscle cramps Bacterial cells produce lactic acid resulting in yoghurt The initial steps from glucose to pyruvate are the same. The enzyme responsible for the production of lactate is lactate dehydrogenase 14 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What are some industrial applications of fermentation? 15 Republic Polytechnic © 2023  Answering the problem statement. OFFICIAL (CLOSED) \ NON-SENSITIVE Why do cells do fermentation? In the absence of oxygen, it is the only way to generate NAD+ so that glycolysis can continue 16 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What have you learned (1)? State that energy is required to maintain life processes and carbohydrates are a major source of food energy Explain glucose is the main carbohydrate that will enter the metabolism that produces energy in the form of ATP molecules Define what is metabolism and identify there are two types of metabolisms: catabolism and anabolism Explain the important steps in glycolysis Recognise that the production of energy can occur even in the absence of oxygen Identify the link between fermentation and glycolysis List some applications of fermentation Compare the ethanol fermentation and fermentation in cells Calculate the amount of products produced from glycolysis and fermentation Calculate the net amount of ATP produced during anaerobic respiration and explain how this ATP is produced 17 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE What have you learned (2)? 18 Republic Polytechnic © 2023  OFFICIAL (CLOSED) \ NON-SENSITIVE Glossary Metabolism- catabolic and anabolic: Aerobic and anaerobic: Glycolysis: Pyruvate ATP (adenosine triphosphate): Nicotinamide adenine dinucleotide (NAD): Fermentation: 19 Republic Polytechnic © 2023