7.2.2.3.1. Alcoholic or ethyl fermentation

Alcoholic or ethyl fermentation

The alcoholic fermentation is a catabolic process of fermentation in the absence of oxygen, by the activity of some microorganisms which process the glucose to obtain as final products: one alcohol, as ethanol (whose chemical formula is CH₃-CH₂-OH), carbon dioxide (CO₂) in the form of gas and adenosine triphosphate (ATP) molecules that are consumed by the microorganisms themselves in their anaerobic cellular energy metabolism. the ethanol. The resulting product is used in the production of some alcoholic beverages, such as wine, beer, cider, cava, etc.

Some yeasts (Fungi kingdom), such as Saccharomyces cerevisiae (beer yeasts) are capable of transforming pyruvic acid into ethanol and carbon dioxide, oxidizing NADH.

All fermentations take place in the cytosol. In alcoholic fermentation, the substrate that is oxidized is glucose that has entered glycolysis, where pyruvate, NADH and ATP have been formed. The pyruvate, after decarboxylation (thus follows CO₂) and reduced (in the reoxidized NADH to NAD) is converted into ethanol.

The production of ethanol is carried out thanks to the enzyme pyruvate decarboxylase, in plant cells, fungi and bacteria.

The alcoholic fermentation or ethylic is anaerobic degradation of glucose to ethanol, originating CO ₂ as a byproduct.

The glucose is oxidized to pyruvic acid, generating NADH. Later two processes happen:

Pyruvic acid decarboxylation, which gives rise to acetaldehyde and CO₂ is released.
Reduction of acetaldehyde to ethanol, thanks to the alcohol-dehydrogenase enzyme, and by consuming the NADH produced in glycolysis.

The energy yield is 2 ATP, the same as in lactic fermentation.

Alcoholic fermentation is carried out mainly by yeasts, highlighting Saccharomyces cerevisiae, which is involved in the production of wine, beer, and in the manufacture of bread. They use glucose, which comes from the hydrolysis of starch in bread and barley in the case of beer.

Logically the bread does not contain alcohol, since the ethanol evaporates with cooking and the CO₂ escapes making the bread fluffy.

In a winery, in which the grape must is fermenting, care must be taken with the CO₂ that is produced, since if it is a closed space without ventilation, CO₂ can displace oxygen and cause suffocation.

Yeasts are facultative aerobic organisms in which the Pasteur effect occurs. If there is O₂, fermentation is inhibited and the pyruvic is fully degraded to CO₂ and water, increasing the energy obtained to 38 ATP per mole, compared to the 2 ATP obtained in fermentation.

By The author of the original version is User:Norro. (Image:Ethanol fermentation de.svg) [GFDL or CC BY-SA 4.0-3.0-2.5-2.0-1.0], via Wikimedia Commons

Curiosity: Rajoy and his "long live the wine".

Learn Biology with the Simpsons: Toast to alcohol.

Curiosity: Animals and fermentation of amarula.

Curiosity: José María Aznar, president of Spain between 1996 and 2004, does not like to be told that he cannot drink if he has to drive .

Questions that have come out in University entrance exams (Selectividad, EBAU, EvAU)

Aragon. June 2018, option A, question 5 .

Biotechnology: (2 points)

a) What do the making of beer and bread have in common? (0.5 points)

b) What is and where does the starting molecule come from? What is and where does the molecule resulting from the basic reaction of these industrial processes go? (1.25 points)

c) Which organism is responsible for this reaction? (0.25 points)

Aragon. June 2009, option B. 5. (2 points).

Read this text carefully and answer the questions indicated at the end.

Beer is an industrial product made from barley. Barley seeds are moistened to germinate, so that when germination begins, their own hydrolytic enzymes break the reserve polysaccharides, (mainly starch), into monosaccharides.

After stopping this process by heat, the malt is obtained. The malt obtained is subjected to the action of yeasts, which initially multiply using the sugars in the medium as a source of carbon and energy. When the oxygen present is consumed, the yeasts start the process that leads to the production of beer.

a) What monosaccharide will originate as a result of the hydrolysis of starch? What types of bonds should the hydrolytic enzymes discussed above break? (0.5 points).

b) What will be the end products of the use of sugars by yeasts, once the oxygen has been consumed? (0.5 points).

c) Compare the efficiency from the energy point of view, of the stage in which the yeasts have oxygen available and the stage in which it has already been consumed. (1 point).

Basque Country, July 2018, option A, question 5.

Bioethanol obtained by fermentation of carbohydrates promises to be the current substitute for gasoline.

a) What types of organisms are capable of producing ethanol from glucose and what is the metabolic advantage of this production? Give reasons for your answer. (0.5 points)

b) Using a diagram, detail the biochemical process to obtain ethanol from glucose. (1 point)

c) What effect would the presence of oxygen have on the process? (0.5 points)

Basque Country, July 2018, option B, question 3.

Applications of microorganisms in Biotechnology:

a) Indicates what the obtaining of bread and wine have in common, at the biochemical process level. Give reasons for your answer. (0.5 points)

b) What biomolecule is used in both processes as starting material and what product is it converted into? What effect would the presence of air have on these processes? Reason for your answers. (1 point)

c) Indicates what type of microorganism is responsible for the biochemical transformations necessary to obtain bread and beer. Is it prokaryotic or eukaryotic? Give reasons for your answer. (0.5 points)

Basque Country, July 2019, option B, question 3

In relation to microorganisms and their applications:

a) (0.5 points). Briefly state what types of microorganisms are used to make bread, beer, and wine.

b) (1 point). It indicates what type of biochemical reactions convert sugars and starches into ethanol. Where does the CO ₂ produced in these reactions come from?

c) (0.5 points). Are they aerobic or anaerobic reactions? Reason for your answers.

Valencian Community, July 2021, question 7.3.

Regarding the industrial production of beer, he explains:

a) Its relationship with fermentation;

b) The microorganisms involved;

c) The substrate on which they act, under what conditions and the final products (3 points)

Fundamental ideas about alcohol fermentation

Alcoholic or ethyl fermentation

The alcoholic fermentation or ethylic is anaerobic degradation of glucose to ethanol, originating CO₂ as a byproduct.
The alcoholic fermentation is a catabolic process of fermentation in the absence of oxygen, consisting of the anaerobic degradation of glucose to ethanol, originating CO₂ as a byproduct.
It is oxidized is glucose (from the hydrolysis of starch in bread or barley in the case of beer) that has entered glycolysis, where pyruvate, NADH and ATP have been formed. The pyruvate, after decarboxylation (e shows CO₂) and reduced (is the reoxidized NADH to NAD) is converted into ethanol.
It is made by some yeasts (Fungi kingdom), such as Saccharomyces cerevisiae (beer yeasts) that intervenes in the production of wine, beer, and in the manufacture of bread.
Energy yield: 2 ATP.
It is carried out in the cytosol.

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Skip navigation Biology 2nd Baccalaureate Biology 2nd Bac. 1. Bioelements and biomolecules. Water and mineral salts 1.1. Chemical bonds in biology 1.1.1. Intramolecular bonds 1.1.1.1. Covalent bond 1.1.1.2. Ionic bond 1.1.2. Intermolecular bonds 1.1.2.1. Van der Waals forces 1.1.2.2. Hydrogen bonds 1.2. The chemical basis of life: inorganic and organic components 1.2.1. Primary bioelements 1.2.2. Secondary bioelements 1.2.3. Trace elements 1.3. The immediate principles or biomolecules 1.3.1. Water 1.3.1.1. Chemical structure of water 1.3.1.2. Properties and functions of water 1.3.2. Mineral salts 1.3.2.1. Functions of salts in solution 1.3.2.2. Colloidal solutions and dispersions 1.3.2.3. Properties of colloidal dispersions 1.3.2.4. Diffusion, osmosis and dialysis 1.3.2.4.1. Diffusion 1.3.2.4.2. Osmosis 1.3.2.4.3. Dialysis 1.4. Bibliography 2. Glucides 2.1. Glucid concept 2.2. Classification of carbohydrates 2.3. Monosaccharides 2.3.1. Trioses 2.3.1.1. Spatial isomerism or stereoisomerism 2.3.2. Tetroses 2.3.3. Pentoses 2.3.3.1. Monosaccharide cyclization 2.3.4. Hexoses 2.4. The N-glucosidic and O-glucosidic bonds 2.4.1. Substances derived from monosaccharides 2.5. Disaccharides 2.6. Polysaccharides 2.6.1. Homopolysaccharides 2.6.1.1. Reserve homopolysaccharides 2.6.1.2. Structural homopolysaccharides 2.6.2. Heteropolysaccharides 2.6.3. Heterosides 2.7. General functions of glucides 2.8. Bibliography 3. Lipids 3.1. Lipid concept 3.2. Classification of lipids 3.2.1. Fatty acids 3.2.1.1. Saturated and unsaturated fatty acids 3.2.1.2. Chemical properties of fatty acids 3.2.1.3. Physical properties of fatty acids 3.2.1.4. Fatty Acid Functions 3.2.2. Saponifiable lipids or with fatty acids 3.2.2.1. Simple lipids 3.2.2.1.1. Acylglycerides 3.2.2.1.2. Cerides 3.2.2.2. Complex lipids 3.2.2.2.1. Phospholipids 3.2.2.2.2. Glycolipids 3.2.3. Unsaponifiable lipids or without fatty acids 3.3. Lipid functions 3.4. Bibliography 4. Proteins 4.1. Introduction to proteins 4.2. Amino acids 4.2.1. Classification of amino acids 4.2.2. Properties of amino acids 4.3. The peptide bond 4.4. Protein 4.4.1. Protein structure 4.4.1.1. Primary structure of proteins 4.4.1.2. Secondary structure of proteins 4.4.1.3. Tertiary structure of proteins 4.4.1.4. Quaternary structure of proteins 4.4.2. Protein properties 4.4.3. Classification of proteins 4.4.3.1. Holoproteins 4.4.3.2. Heteroproteins 4.4.4. Protein functions 4.5. Enzymes 4.5.1. Structure of enzymes 4.5.2. The active center of enzymes 4.5.3. General Mechanism of Enzyme Catalysis 4.5.4. Regulation of enzyme activity 4.5.5. Allosteric enzymes 4.5.6. Nomenclature and classification of enzymes 4.6. The vitamins 4.6.1. Fat-soluble vitamins 4.6.2. Water soluble vitamins 4.7. Bibliography 5. Nucleotides and nucleic acids 5.1. The chemical composition of nucleic acids 5.1.1. Components of nucleic acids 5.1.2. Concept, types and functions of nucleic acids 5.1.3. Nucleosides 5.1.4. Nucleotides 5.1.4.1. Nucleotide functions 5.1.5. Nucleic acids 5.2. Deoxyribonucleic acid (DNA) 5.2.1. DNA structure 5.2.1.1. Primary structure of DNA 5.2.1.2. Secondary structure of DNA 5.2.1.3. Tertiary structure of DNA 5.2.1.3.1. Tertiary structure of DNA in prokaryotes 5.2.1.3.2. Tertiary structure of DNA in eukaryotes 5.2.1.4. Quaternary structure of DNA 5.2.2. DNA types 5.2.3. Genetic material: chromatin and chromosomes 5.2.3.1. Karyotype and karyogram 5.3. Ribonucleic acid (RNA) 5.3.1. RNA types 5.3.1.1. Transfer RNA 5.3.1.2. Messenger RNA 5.3.1.3. Ribosomal RNA 5.3.1.4. Nucleolar RNA 5.3.1.5. Small nuclear RNA 5.3.2. Functions of ribonucleic acids 5.4. Bibliography 6. Cell morphology 6.1. Cell concept 6.1.1. Cell history 6.1.2. Cell theory 6.2. Levels of cellular organization 6.2.1. General characteristics of cells 6.2.2. Prokaryotic cells 6.2.2.1. Prokaryotic cell morphology 6.2.2.2. Structure of prokaryotes 6.2.2.2.1. Bacterial capsule 6.2.2.2.2. Bacterial wall 6.2.2.2.3. Plasma membrane 6.2.2.2.4. Cytoplasm-Ribosomes-Inclusions 6.2.2.2.5. Bacterial DNA 6.2.2.2.6. Bacterial appendages 6.2.2.3. Bacteria Physiology 6.2.3. Eukaryotic cells 6.2.3.1. Animal and plant cell 6.2.3.1.1. Animal eukaryotic cell 6.2.3.1.2. Plant eukaryotic cell 6.2.3.2. Cell Evolution: Endosymbiont Theory 6.3. Size, shape and quantity 6.4. The plasma membrane 6.4.1. Chemical composition of the membrane 6.4.2. The structure of the membrane. The fluid mosaic model 6.4.3. Functions of the plasma membrane 6.4.4. Transport across the membrane 6.4.4.1. Small molecule transport 6.4.4.2. Macromolecule transport 6.4.5. Plasma membrane differentiations 6.5. The cell wall of plant cells 6.5.1. Chemical composition of the cell wall 6.5.2. Cell wall structure 6.5.3. Cell wall differentiations 6.5.4. Cell wall functions 6.6. Extracellular matrix or glucocalyx 6.7. Cytosol or hyaloplasm 6.8. The cytoskeleton 6.8.1. Microfilaments or actin filaments 6.8.2. Intermediate filaments 6.8.3. Microtubules 6.9. Cell membrane and organelle systems 6.9.1. Membrane systems 6.9.1.1. The endoplasmic reticulum 6.9.1.2. Golgi apparatus 6.9.2. Cell organelles 6.9.2.1. Lysosomes 6.9.2.2. Peroxisomes 6.9.2.3. Vacuoles 6.9.2.4. Mitochondria 6.9.2.4.1. Functions of the mitochondria 6.9.2.5. Plastids 6.9.2.5.1. Chloroplasts 6.9.2.6. Ribosomes 6.9.2.7. Centrosome 6.9.2.8. Cilia and flagella 6.10. Cell motility 6.11. The cell nucleus 6.11.1. Characteristics of the cell nucleus 6.11.2. The interphase nucleus 6.11.3. The mitotic nucleus or nucleus in division 6.12. Bibliography 7. Metabolism 7.1. Metabolism 7.1.1. Energetic Aspects of Cellular Chemical Reactions 7.2. Catabolism 7.2.1. Catabolism and obtaining energy 7.2.2. Carbohydrate catabolism 7.2.2.1. Glycolysis 7.2.2.2. Cellular respiration 7.2.2.2.1. Oxidative decarboxylation 7.2.2.2.2. Krebs cycle 7.2.2.2.3. Electron transport chain 7.2.2.2.4. Energy balance of cellular respiration 7.2.2.3. Fermentations 7.2.2.3.1. Alcoholic or ethyl fermentation 7.2.2.3.2. Lactic fermentation 7.2.2.3.3. Other types of fermentations 7.3. Anabolism 7.3.1. Autotrophic anabolism 7.3.2. Photosynthesis 7.3.2.1. Photochemical or light phase 7.3.2.1.1. Photosystems 7.3.2.1.2. Photophosphorylation 7.3.2.1.2.1. Non cyclic photophosphorylation 7.3.2.1.2.2. Cyclic photophosphorylation 7.3.2.2. Biosynthetic or dark phase 7.3.2.3. Factors influencing photosynthesis 7.3.2.4. Products of photosynthesis 7.3.3. Chemosynthesis 7.4. Bibliography 8. Cell reproduction 8.1. The cell cycle 8.1.1. Interphase 8.1.2. Cellular division 8.2. Cellular division 8.2.1. Mitosis 8.2.1.1. Prophase 8.2.1.2. Metaphase 8.2.1.3. Anaphase 8.2.1.4. Telophase 8.2.1.5. Cytokinesis 8.2.1.6. More on mitosis 8.2.2. Meiosis 8.2.2.1. Meiosis I 8.2.2.2. Meiosis II 8.2.3. Meiosis and sexual reproduction 8.2.4. Meiosis and life cycle 8.2.5. Biological importance of meiosis 8.3. Differences and similarities between mitosis and meiosis 8.4. Bibliography 9. Classical genetics 9.1. Genetics basics 9.2. Mendelian genetics 9.2.1. The method 9.2.2. Mendel's Laws 9.2.2.1. Mendel's first law or principle of uniformity in the first generation 9.2.2.2. Mendel's second law or principle of segregation 9.2.2.2.1. Backcross and test crossover 9.2.2.3. Mendel's third law or principle of independent combination 9.3. Gene interaction 9.3.1. Gene interaction between allelic genes 9.3.2. Gene interaction between non-allelic genes that influence for the same trait 9.4. Chromosomal theory of heredity 9.5. Ligation and recombination 9.6. Complex mendelism 9.6.1. Multiple allelism 9.6.1.1. Lethal genes 9.6.2. Pleiotropy 9.6.3. Expressiveness and genetic penetrance 9.7. Sex-linked inheritance 9.7.1. Y-linked inheritance 9.7.2. X-linked inheritance 9.8. Heredity influenced by sex 9.9. Bibliography 10. Molecular genetics 10.1. DNA as hereditary material 10.2. DNA replication 10.2.1. The need for DNA replication 10.2.2. First hypotheses about DNA duplication 10.2.3. Meselson and Stahl experiment 10.2.4. The sense of growth of the new strands 10.2.5. Mechanism of DNA replication 10.2.5.1. Replication in prokaryotes 10.2.5.2. Replication in eukaryotes 10.2.6. Error correction 10.2.7. Enzymes involved in replication 10.3. Gene concept 10.4. "One gene-one enzyme" theory 10.5. Transcription 10.5.1. Mechanism of transcription 10.5.1.1. Transcription in prokaryotes 10.5.1.2. Eukaryotic transcription 10.6. Translation or protein biosynthesis 10.6.1. The genetic code 10.6.2. Mechanism of translation of RNA to proteins 10.6.2.1. Translation in eukaryotes 10.7. Regulation of gene expression 10.8. Bibliography 11. Genetics and evolution 11.1. Mutations 11.2. Types of mutations 11.2.1. Gene or point mutation 11.2.2. Chromosomal or structural mutation 11.2.3. Mutation at the genomic level 11.3. Causes of mutations 11.4. Evolutionary implications of mutations 11.5. Metabolic implications of mutations 11.6. Bibliography 12. Microbiology and biotechnology 12.1. Microbiology 12.2. Viruses 12.2.1. Viral morphology 12.2.2. Viral physiology 12.2.2.1. Lytic cycle 12.2.2.2. Lysogenic cycle 12.2.2.3. Cycles of viruses of special interest 12.2.2.3.1. Flu virus life cycle 12.2.2.3.2. Life cycle of the AIDS virus 12.3. Other acellular forms 12.3.1. Viroids 12.3.2. Prions 12.4. Biotechnology 12.5. Bibliography 13. Immunology 13.1. Infection concept 13.2. Defense mechanisms against infections 13.2.1. Nonspecific mechanisms 13.2.1.1. Primary barriers: external defenses 13.2.1.2. Secondary barriers: internal defenses 13.2.2. Specific mechanisms 13.3. Immunity and immune system 13.3.1. Components of the immune system 13.3.2. Concept and nature of antigens 13.4. The immune response 13.4.1. Humoral immune response: the antibodies 13.4.1.1. Antibody-producing cells: B lymphocytes 13.4.1.2. Antibodies 13.4.1.2.1. Types of antibodies 13.4.1.2.2. Antigen-antibody reaction 13.4.1.3. Immune memory: primary and secondary responses 13.4.2. Cellular immune response: T lymphocytes 13.5. Types of immunity 13.5.1. Natural immunity 13.5.2. Artificial immunity 13.6. Immune system disorders 13.6.1. Autoimmunity 13.6.2. Hypersensitivity 13.6.3. Immunodeficiency 13.6.4. Transplants and the phenomenon of rejections 13.7. Bibliography « Previous \| Next » 7.2.2.3.1. Alcoholic or ethyl fermentation Alcoholic or ethyl fermentation The alcoholic fermentation is a catabolic process of fermentation in the absence of oxygen, by the activity of some microorganisms which process the glucose to obtain as final products: one alcohol, as ethanol (whose chemical formula is CH₃-CH₂-OH), carbon dioxide (CO₂) in the form of gas and adenosine triphosphate (ATP) molecules that are consumed by the microorganisms themselves in their anaerobic cellular energy metabolism. the ethanol. The resulting product is used in the production of some alcoholic beverages, such as wine, beer, cider, cava, etc. Some yeasts (Fungi kingdom), such as Saccharomyces cerevisiae (beer yeasts) are capable of transforming pyruvic acid into ethanol and carbon dioxide, oxidizing NADH. All fermentations take place in the cytosol. In alcoholic fermentation, the substrate that is oxidized is glucose that has entered glycolysis, where pyruvate, NADH and ATP have been formed. The pyruvate, after decarboxylation (thus follows CO₂) and reduced (in the reoxidized NADH to NAD) is converted into ethanol. The production of ethanol is carried out thanks to the enzyme pyruvate decarboxylase, in plant cells, fungi and bacteria. The *alcoholic fermentation or ethylic* is anaerobic degradation of glucose to ethanol, originating CO ₂ as a byproduct. The glucose is oxidized to pyruvic acid, generating NADH. Later two processes happen: Pyruvic acid decarboxylation, which gives rise to acetaldehyde and CO₂ is released. Reduction of acetaldehyde to ethanol, thanks to the alcohol-dehydrogenase enzyme, and by consuming the NADH produced in glycolysis. The energy yield is 2 ATP, the same as in lactic fermentation. Alcoholic fermentation is carried out mainly by yeasts, highlighting Saccharomyces cerevisiae, which is involved in the production of wine, beer, and in the manufacture of bread. They use glucose, which comes from the hydrolysis of starch in bread and barley in the case of beer. Logically the bread does not contain alcohol, since the ethanol evaporates with cooking and the CO₂ escapes making the bread fluffy. In a winery, in which the grape must is fermenting, care must be taken with the CO₂ that is produced, since if it is a closed space without ventilation, CO₂ can displace oxygen and cause suffocation. Yeasts are facultative aerobic organisms in which the Pasteur effect occurs. If there is O₂, fermentation is inhibited and the pyruvic is fully degraded to CO₂ and water, increasing the energy obtained to 38 ATP per mole, compared to the 2 ATP obtained in fermentation. By The author of the original version is User:Norro. (Image:Ethanol fermentation de.svg) [GFDL or CC BY-SA 4.0-3.0-2.5-2.0-1.0], via Wikimedia Commons Curiosity: Rajoy and his "long live the wine". Learn Biology with the Simpsons: Toast to alcohol. Curiosity: Animals and fermentation of amarula. Curiosity: José María Aznar, president of Spain between 1996 and 2004, does not like to be told that he cannot drink if he has to drive . Questions that have come out in University entrance exams (Selectividad, EBAU, EvAU) Aragon. June 2018, option A, question 5 . Biotechnology: (2 points) a) What do the making of beer and bread have in common? (0.5 points) b) What is and where does the starting molecule come from? What is and where does the molecule resulting from the basic reaction of these industrial processes go? (1.25 points) c) Which organism is responsible for this reaction? (0.25 points) Aragon. June 2009, option B. 5. (2 points). Read this text carefully and answer the questions indicated at the end. Beer is an industrial product made from barley. Barley seeds are moistened to germinate, so that when germination begins, their own hydrolytic enzymes break the reserve polysaccharides, (mainly starch), into monosaccharides. After stopping this process by heat, the malt is obtained. The malt obtained is subjected to the action of yeasts, which initially multiply using the sugars in the medium as a source of carbon and energy. When the oxygen present is consumed, the yeasts start the process that leads to the production of beer. a) What monosaccharide will originate as a result of the hydrolysis of starch? What types of bonds should the hydrolytic enzymes discussed above break? (0.5 points). b) What will be the end products of the use of sugars by yeasts, once the oxygen has been consumed? (0.5 points). c) Compare the efficiency from the energy point of view, of the stage in which the yeasts have oxygen available and the stage in which it has already been consumed. (1 point). Basque Country, July 2018, option A, question 5. Bioethanol obtained by fermentation of carbohydrates promises to be the current substitute for gasoline. a) What types of organisms are capable of producing ethanol from glucose and what is the metabolic advantage of this production? Give reasons for your answer. (0.5 points) b) Using a diagram, detail the biochemical process to obtain ethanol from glucose. (1 point) c) What effect would the presence of oxygen have on the process? (0.5 points) Basque Country, July 2018, option B, question 3. Applications of microorganisms in Biotechnology: a) Indicates what the obtaining of bread and wine have in common, at the biochemical process level. Give reasons for your answer. (0.5 points) b) What biomolecule is used in both processes as starting material and what product is it converted into? What effect would the presence of air have on these processes? Reason for your answers. (1 point) c) Indicates what type of microorganism is responsible for the biochemical transformations necessary to obtain bread and beer. Is it prokaryotic or eukaryotic? Give reasons for your answer. (0.5 points) Basque Country, July 2019, option B, question 3 In relation to microorganisms and their applications: a) (0.5 points). Briefly state what types of microorganisms are used to make bread, beer, and wine. b) (1 point). It indicates what type of biochemical reactions convert sugars and starches into ethanol. Where does the CO ₂ produced in these reactions come from? c) (0.5 points). Are they aerobic or anaerobic reactions? Reason for your answers. Valencian Community, July 2021, question 7.3. Regarding the industrial production of beer, he explains: a) Its relationship with fermentation; b) The microorganisms involved; c) The substrate on which they act, under what conditions and the final products (3 points) Fundamental ideas about alcohol fermentation Alcoholic or ethyl fermentation The *alcoholic fermentation or ethylic* is anaerobic degradation of glucose to ethanol, originating CO₂ as a byproduct. The alcoholic fermentation is a catabolic process of fermentation in the absence of oxygen, consisting of the anaerobic degradation of glucose to ethanol, originating CO₂ as a byproduct. It is oxidized is glucose (from the hydrolysis of starch in bread or barley in the case of beer) that has entered glycolysis, where pyruvate, NADH and ATP have been formed. The pyruvate, after decarboxylation (e shows CO₂) and reduced (is the reoxidized NADH to NAD) is converted into ethanol. It is made by some yeasts (Fungi kingdom), such as Saccharomyces cerevisiae (beer yeasts) that intervenes in the production of wine, beer, and in the manufacture of bread. Energy yield: 2 ATP. It is carried out in the cytosol. Licensed under the Creative Commons Attribution Share Alike License 4.0 « Previous \| Next » These pages are semi-automatically translated from the web Biology 2nd Baccalaureate. Biología de 2º de Bachillerato (biologia-geologia.com). You can make any suggestion, question, comment, ..., in our forum 2º Bachillerato Biología - Foro de biologia-geologia.com
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Alcoholic or ethyl fermentation

Alcoholic or ethyl fermentation