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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , CHAPTER NO: 13, , RESPIRATION, AND ENERGY TRANSFER, Respiration:, o The oxidation of organic compounds in living cells to release energy to, synthesize ATP molecules called as respiration., o Catabolism [breakdown] or oxidation of food material into simpler, substance to liberate energy is called as respiration., o The process which involves oxidation of organic food material to release, energy in the form of ATP., o The biological oxidation of organic substances include stepwise, breakdown of organic substances to release energy to synthesize ATP, Molecules., o Intracellular process of oxidation in which complex organic substances, are broken down in stepwise manner to release energy in the form of, ATP, o Respiratory substrate: CHO(glucose),proteins, fats and organic acid –, forms of potential energy. Glucose is most preferred substrate due to, availability and acceptance by all kinds of organisms., o Byproduct: CO2 and H2O, , ATP: Currency of energy, , o Definition: ATP is a triphosphate ester of adenosine ribonucleoside, which is an energy rich chemical compound., o Chemical composition:, 1. Adenine - nitrogen purine base, 2. Ribose(C5H10O5)- Pentose sugar, 3. Phosphate groups (3), Adenosine ribonucleoside= Adenine + Ribose, , o Formation of ATP:, , 1. Adenosine ribonucleoside=, 2. Adenosine + 1 phosphate =, 3. AMP + 2nd phosphate, =, 4. ADP + 3rd phosphate, =, o Energy conversion:, 1 RESPIRATION, , Adenine + Ribose, Adenosine monophosphate(AMP), Adenosine diphosphate (ADP), Adenosine triphosphate (ATP), |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 1. During release of energy: ADP & IP converted into ATP., ADP + IP-------------------- ATP., , 2. During requirement of energy: ATP hydrolyzed into ADP & IP. During, hydrolysis, high energy phosphate bond broken and energy released in, the form of ADP and IP, Hydrolysis, ATP ------------------------- ADP + IP, , 3. Most of energy conversion in the cell is at ADP & ATP level., 4. ATP stores energy released during respiration in its high energy, chemical bonds. The energy used for various cellular activities (Division,, growth, movement, reproduction and biosynthesis., 5. On hydrolysis of an ATP molecule,7.3 kcal energy is released., , Mitochondria:, , o Definition: The filamentous or rod shaped structure which is selfregulating, self-duplicating, semi autonomous living cell organelle., Mitochondria is a site for respiration i.e. ATP synthesis, o Location: Cytoplasm of eukaryotic cell., o Length :1-4 µ Width : 0.5-10µ, , o Ultra structure:, , 1. Membranes: Double membrane bound cell organelles., a. Outer membrane: It is smooth thin, tightly stretched, without folding, and freely permeable. It is not associated with ATP synthesis, b. Inner membrane: It is rough, thick, with folding and differentially, permeable membrane. it is associated with ATP synthesis., o Crista: Each fold of inner membrane forms finger like projections is, called as crista.Cristae bears number of stalked particles called as F 1, particles., o F1 particles/Oxysome: Tennis racket shaped particles present on, ‘m’face (facing matrix) of criste called as oxysomes/ F1, particles/elementary particles. The electron carriers of ETS and enzymes, required for ATP synthesis located on the body of oxysomes .Oxysomes, helps in oxidative phosphorylation /ATP synthesis., , 2 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 2. Chambers:, a. Outer chamber: It is present between outer and inner membrane., b. Inner chamber: It is surrounded by inner membrane and contains, matrix., 3. Matrix: The liquid present in inner chamber is called as matrix .Matrix, contains - a) DNA(single circular, b) RNA, c) Ribosomes(70’s type), d)Respiratory pigments e) Respiratory enzymes and co enzymes., , o Functions:, , 1. Release of energy: Mitochondria release energy in the form of ATP so called, as power houses of cells., 2. Storage of energy: The energy in the form of ATP is stored and used for, various cellular activities., 3. Helps in aerobic respiration: Mitochondria helps in aerobic respiration and, releases energy., 4. Helps in Kreb's cycle: Respiratory enzymes required for Krebs’s cycle, 5. Helps in oxidative Phosphorylation: Mitochondria helps in oxidative, phosphorylation, 6. Protein synthesis: Mitochondria also help in protein synthesis because they, contain DNA, RNA and ribosome., 7. Helps in terminal oxidation and electron transport: oxysomes /F1 particles, of criste helps in terminal oxidation., B. Types: A) Aerobic respiration, B) Anaerobic respiration, , Points, , Aerobic respiration, , Anaerobic respiration, , 1. Definition, , Respiration in the, presence of free molecular, O2, Cytoplasm and, mitochondria, CO2 and H2O, Non -Toxic, , Respiration in the absence, of free molecular O2, , Large quantity, (686Kcal/Glucose mol.), Complete oxidation, , Small quantity, (50.4Kcal/Glucose mol.), Incomplete oxidation, , 38 ATP, , 2ATP, , 6, , 2, , All eukaryotic cells, 1.Glycolysis, 2.Krebs’s cycle 3.ETS, C6H12O6+6O2----6CO2+6H2O +38ATP, Higher plants and animals, , Most of prokaryotic cells, 1.Glycolysis, 2.Fermentation, C6H12O6-----2C2H5OH+2CO2, +2ATP, Most of prokaryotic cells,, some bacterial cells and, animal muscles, , 2. Place of, occurrence, 3. 4.End product, 4. .Nature of end, product, 5. Amount of, energy released, 6. Nature of, oxidation, 7. No. of ATP mol., released/glucos, e mol., 8. No. of CO2 mol., given out, 9. Nature of cells, 10. Phases, 11., , Equation, , 12., , Examples, , 3 RESPIRATION, , |, , Cytoplasm, Ethyl alcohol and lactic acid, Less toxic, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , S Points, N, , Chloroplast, , Mitochondria, , 1, , In all green plants, Green, Photosynthetic apparatus, , In all living organism, except prokaryotic cells, colorless, Power house of cells, , Photosynthesis, Synthesis of glucose, , Kreb’s cycle and ATP, Breakdown of glucose, , Smooth outer and inner, membrane, By photophosphrylation, , Smooth outer and folded, inner membrane, By oxidative, phosphorylation, Catabolic process, , 2, 3, 4, 5, 6, 7, 8, , Place of, occurance, Color, Identification, mark, Carrying out, Effect of, glucose, Membranes, Synthesis of, ATP, Nature, , Points, 1. Definition, , 2. Nature of, process, 3. Role of oxygen, 4. Role of CO2, 5. Time limit, 6. Raw material, required, 7. End products, 8. Place of, occurrence, 9. Chlorophyll, 10. Effect on, energy, 11. Dependence, of light, 12. Synthesis, of ATP, 13. Dry weight, of plants, , Anabolic process, Photosynthesis, The process in which green, plants synthesized their own, food by using simple, inorganic material(CO2 & H2O, ) with the help of light, Anabolic(Building up), Given out, Taken in, Day time, CO2 & H2O, , Respiration, The process which, involves oxidation of, organic food material to, release energy in the, form of ATP, Catabolic(Breaking, down), Taken out, Given out, Day and night time, Glucose & O2, , Glucose & O2, Only in green cells with, chloroplast, Necessary, Energy is absorbed, , CO2 & H2O, Green as well as nongreen cells, Not necessary, Energy is released, , Present, , Absent, , By photophosphrylation, , By oxidative, Phosphorylation, Decreased, , Increased, , Anaerobic respiration is less efficient than aerobic, respiration, , 1. Release of energy (Kcal): In aerobic respiration,686 Kcal energy, released and in anaerobic respiration only 50.4 Kcal energy released, from each molecule of glucose., 2. No. of CO2 molecules released: In aerobic respiration 6 molecules of, CO2 are released and in anaerobic respiration only 2 molecules of CO2, are released., 4 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 3. No. of ATP molecules formed: In aerobic respiration, 38 molecules of, ATP formed from 1 molecule of glucose and in anaerobic respiration, only 2 molecules of ATP formed., 4. Oxidation of glucose: In aerobic respiration, complete oxidation of, glucose and in anaerobic, there is incomplete oxidation of glucose., From above the information, it is clear that anaerobic respiration is, less efficient than aerobic respiration, , Types:, , A. Aerobic respiration, , B. Anaerobic respiration, , A) Aerobic respiration :, Definition: Respiration in the presence of free molecular O2 is called as, aerobic respiration, Stages/Phases: 1.Glycolysis 2. Krebs’s cycle 3. Electron transfer, , 1) Glycolysis/EMP pathway:, Definition: Stepwise enzymatic breakdown of glucose molecules into two, , molecules of pyruvic acid is called as glycolysis., EMP pathway: Glycolysis discovered by 3 German scientists i.e, 1. Embeden, 2.Meyer Hof, 3.Parnas, Common Pathway: EMP pathway is common for aerobic and anaerobic, respiration. There is common breakdown of glucose., Place of occurrence: only in cytoplasm of cell [ cytoplasmic respiration ], Role of Oxygen: EMP pathway takes place in absence of molecular O2, Mechanism:, A) Preparatory phase & Cleavage: Initial phase of glycolysis includes, phosphorylation and cleavage and results into formation of 2 PGAL mol., 1. Phosphorylation(Phosphorylation of glucose to glucose 6 phosphate), : The glucose undergoes Phosphorylation by using ATP molecules under, the influence of enzyme hexokinase and there is formation of glucose 6, phosphate and ADP.(The phosphate from ATP attached to carbon no.6, of glucose and glucose 6 phosphate formed), Phosphorylation, Glucose +ATP ------------------------------ Glucose 6 phosphate + ADP, Hexokinase + Mg++, 2. Isomerization (Glucose 6 phosphate to fructose 6 phosphate):Glucose, 6 phosphate undergoes isomerization in the presence of enzyme phospho, gluco kinase and there is formation of fructose 6 phosphate, Isomerization, Glucose 6 Phosphate -------------------------- Fructose 6 phosphate, phospho gluco isomerase, 3. Phosphorylation II(Phosphorylation of fructose 6 phosphate to, fructose1,6 diphosphate): Fructose 6 phosphate undergoes, phosphorylation in the presence of enzyme phospho fructo kinase and, there is formation of fructose1,6 diphosphate. In this process ATP is used, and converted into ADP., Phosphorylation, Fructose 6 + ATP --------------------------------Fructose 1,6 + ADP, Phosphate, phospho fructo kinase + Mg++, diphosphate, 5 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , Number of Pyruvic acid molecules: At the end of glycolysis from 1, , glucose molecules, 2 pyruvic acid molecules formed because after, cleavage of fructose 1,6 diphosphate ,there is formation of DHAP And, 3PGAL.DHAP also undergoes isomerization and there is also formation of, 3PGAL.From this two reactions 2 molecules of 3PGAL formed and from, each 2PGAL ,there is formation of 2 PGA molecules. From 2 PGA, molecules 2 molecules of PA formed at the end of Glycolysis., Total no of ATP molecules formed in glycolysis:, 1. Total 4 ATP molecules are formed in glycolysis., a) Dephosphorylation I(Step 7), = 2 ATP, b) Dephosphorylation II(Step 10) = 2 ATP, 2. 2 ATP molecules are utilized in reaction 1and 3 (phosphorylation), 3. So, finally 2 ATP molecules are formed., 4. Therefore in actual process of glycolysis, breakdown of glucose, forms 2 ATP molecules., NADH2 generation: Oxidative phosphorylation[Step 6] = 2 NADH2, Net gain of ATP molecules In glycolysis:, 1. 2 ATP in actual process of glycolysis when there is breakdown of, glucose to PA., 2. 6 ATP by ETS in glycolysis .NAD molecules used in oxidative, phosphorylation and converted into NADH2 .The NADH2 forms 3, ATP molecules. In this,2 NADH2 molecules present so 6 ATP, molecules generation. So in this way, net gain of ATP in glycolysis, is 8 ATP., Reaction of glycolysis :, Glycolysis, Glucose + 2NAD + 2ADP +2IP, 2PA +2 NADH 2 + 2 ATP, Significance:, 1. Formation of 2 molecules of PA: In glycolysis, there is ---2. Formation of 2 molecules of NADH2, 3. Formation of 2 molecules of ATP:, 4. Net gain of ATP: In glycolysis there is net gain of 8 ATP molecules i.e. 2, ATP from breakdown of glucose and 6 ATP from 2 molecules of NADH 2., 5. Incomplete oxidation of glucose: In glycolysis, there is incomplete, oxidation of glucose without use of atmospheric oxygen., 6. Formation of intermediate compound: Glycolysis helps in fat and, protein metabolism., , Phase II/Link reaction/Oxidative decarboxylation /Acetelation, , of pyruvate : PA undergoes oxidative decarboxylation in the presence of, enzyme pyruvate dehydrogenase and there is formation of acetyl Co.A, OR Removal of CO2 along with oxidation by removal of hydrogen in the, presense of of enzyme pyruvate dehydrogenase (oxidase) and there is, formation of acetyl Co.A, Oxidative decarboxylation, 2 PA+ 2NAD+, 2CO 2 + 2NADH2+, 2 Co. A, Pyruvate dehydrogenase, 2Acetyl Co. A, 8 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , In this step 2 reactions work simultaneously i.e. oxidation and, decarboxylation, a) Oxidation: Removal of H2 from PA with the help of NAD and NAD, converted into NADH2, b) Decarboxylation: CO2 is removed from PA and there is Carboxylation, of PA. After oxidative decarboxylation, PA is converted into, Acetyl.Acetyl fraction combines with co enzyme A and there is, formation of Acetyl co enzyme A in the mitochondrial matrix., , 2)Kreb’s cycle/TCA cycle/Citric acid cycle:, o Definition: The process which involves further breakdown of PA into CO2, and H2O is called as kreb’s cycle. Sir Hans Krebs discovered this cycle so, called as Krebs’s cycle., o Complete oxidation of Acetyl Co. enzyme and release of CO2 in, stepwise manner .During reactions, Co enzymes NAD and FAD takes up, H2 or 2H + removed during oxidation and NADH2 and FADH2 formed., o TCA (Tricarboxylic acid cycle):The many organic acids formed during, this cycle and each contains 3 carboxyl groups(-COOH) so called as TCA, cycle., o Citric acid cycle: The first stable compound formed in Krebs’s cycle is, citric acid so also called as citric acid cycle., o Place of occurrence: Matrix of mitochondria., o Mechanism: 2 molecules of pyruvic acid/pyruvate formed at the end of, glycolysis .Therefore Kreb’s cycle repeated twice for oxidation of every, glucose molecule. Due to 2 turns ,6 NADH2,6 FADH2 ,2 ATP molecules, and 3 molecules of H2O used up and 2 molecules of CO2released, 1. Oxidative decarboxylation of PA: PA undergoes oxidative, decarboxylation in the presence of enzyme pyruvate dehydrogenase and, there is formation of acetyl., Oxidative decarboxylation, 2 PA+ 2NAD --------------------------------------2 Acetyl +2NADH2+2 CO2, Pyruvate dehydrogenase, 2. Formation of Acetyl Co.A: Acetyl combines with co-enzyme A and, there is formation of Acetyl Co.A., Combination, 2Acetyl+2 Co.A ------------------------------ 2Acetyl Co.A, , Reactions of Krebs cycle:, , 1. Condensation of Acetyl Co.A with OAA: Acetyl Co.A combines with, OAA in the presence of enzyme citric acid synthetase and there is, formation of Citric acid Combination, Acetyl Co.A +OAA+ H2O -------------------Citric acid/Citrate + Co.A, 2. Isomerization of citric acid to isocitric acid: Citric acid undergoes, isomerization and there is formation of isocitric acid., Isomerization involves two reactions i.e. dehydration and hydration., a) Dehydration of Citrate/Citric acid: Citric acid undergoes dehydration, in the presence of aconitase isomerase and there is formation of Cis, aconitic acid and H2O, 9 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 3. Formation of 2FADH2:, 4. Formation of intermediate compound: Intermediate compounds, acts as starting material for synthesis of many other organic, compounds., 5. Complete oxidation of PA: In oxidation,H2 is removed and removed, H2 joins to O2 and there is formation of H2O and this is called terminal, oxidation., H2 + 1/2 O2 ------------------ H2O, 6. Regeneration of OAA:, 7. Release of 6 CO2 and 6 H2O molecules: (Reaction no 7 and 8), , 3) Electron transport system/E.T.S./ Terminal oxidation:, Definition: The oxidative process in which hydrogen is remove, progressively from respiratory substrate (glucose) is called as electron, transport system Or, Oxidation of reduced co enzymes, into their oxidized forms called ETS., Role Of H2 removed: The hydrogen removed from respiratory substrate, does not combine with O2 directly but it is transported through ETS/ETC, or respiratory chain., The hydrogen ion ionizes into photons and electrons. The, photons released in mitochondrial matrix but electrons channeled, through ETS, Place of occurrence: Inner membrane of mitochondria (on cristae), Elements of ETS, 1. NAD: Nicotinamide adenine dinucleotide, 2. FAD: Flavin adenine dinucleotide, 3. Cytochromes(Electron Carriers) :Cyt.b , Cyt.c1 , Cyt.c Cyt.a ,, Cyt.a3, 4. Co.enzymes: FMN,Red Co.Q. [Ubiquinone], , , Mechanism: In glycolysis and Kreb’s cycle , oxidatio/dehydrogenation, , takes place and NAD and FAD reduced into NADH2 and FADH2 .These, reduced co enzymes are converted back into their oxidized form., Synthesis of ATP takes place with the help of energy released during, electron transfer. Free molecular O2 is final acceptor of electrons., Oxysomes plays important role in ETS. Electron carrier arranged on the, body of oxysomes in order to their decreasing energy level., 1. Role of NAD/FAD : During process of respiration, 2 H2 atoms are, removed from respiratory substrate glucose and accepted by NAD or FAD, .NAD is reduced to NADH2 or FAD reduced to FADH2., Respiratory substrate, NAD+ H2 ---------------------- NADH2. Or, (Glucose), FAD+ H2 ---------------------- FADH2., 2. Role of NADH2 /FADH2 : NADH2 enters in ETS. NADH2.is oxidized to, NAD with removal of H2., NADH2--------------------- NAD + H2, FADH2 enters in ETS. FADH2.is oxidized to FAD with removal of H2., 13 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 10. ATP generation steps : Biosynthesis of ATP molecules using energy, released during oxidation of respiratory substrate called as oxidative, phosphorylation., a. Step1: When there is transfer of H2 with ē from NADH2 to FAD, there, is generation of ATP, b. Step2: When there is transfer of H2 with ē from cyt.b to cyt.c., c. Step 3: When there is transfer of H2 with ē from cyt.a to cyt.a3., 11. Terminal oxidation: The process in which H2 from cyt.a3 is passed to, molecular O2 and there is formation of H2O is called as terminal, oxidation. Or two electrons react with atmospheric O2 to produce O—, which joint with 2H+ molecules to produce water., Oxygen is last electron acceptor in ETS. At the end of ETS ,H2 react, with atmospheric O2 to form water molecule called as metabolic water., ½ O2 +2 ē ---------------------- ½ O2, 2H+ ½ O2 --------------------- H2O, Summary equation of ETS:, Glucose ------H2 -------ETS--------- O2 ----------------H2O, Significance:, 1. Synthesis of ATP: In ETS, some energy from ē is used for formation of, ATP by using ADP & IP [34 ATP molecules produced through ETS out of, 38 ATP], ē, ADP+IP ---------------- ATP, 2. Formation of metabolic H2O: In terminal oxidation, H2 combines with, O2 and there is formation of H2O.The water formed is called as metabolic, water. In this way O2 is last electron acceptor in ETS., 3. Complete oxidation of substrate: ETS helps in complete oxidation of, substrate because O2 is available to accept H2 and there is formation of, H2O, 4. Prevention of damage cells: Energy is released step by step so prevents, cell damage., 5. Energy from ETS: energy from ETS is used by various cells for cellular, activities., 6. No. of ATP molecules released by H2 or electron pair in ETS: 3 ATP, molecules are released in ETS., 7. Provides H2O necessory for Kreb’s Cycle., 8. Regenerates oxidized co enzymes(NAD & FAD)\, , B) Anaerobic respiration:, 1. Definition: The process of respiration takes place in the absence of free, molecular oxygen is called as anaerobic respiration. Or, Incomplete oxidation of the respiratory substrate in the absense of, oxygen to yield CO2 & ethyl alcohol., 2. Place of Occurrence: No. of Bacteria , Yeast and many other organisms, without mitochondria in cytoplasm., 3. Mechanism :, 15 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 1. Glycolysis (Degradation of glucose):Glycolysis is common for aerobic, and anaerobic respiration .In glycolysis, there is breakdown of glucose, and 2 molecules of PA,2 molecules of ATP ad 2 molecules of NADH2 are, formed ., Glycolysis, C6H12O6+ 2NAD+ ------------------2CH3-CO-COOH + 2NADH2, (Glucose), 2ADP+IP, (pyruvate ), +2ATP, 2. Decarboxylation of PA to acetalaldehyde: PA dose not enter in Krebs, cycle because of absence of free molecular O2., The PA undergoes decarboxylation the presence of enzyme pyruvate, decarboxylase and there is formation of acetylaldehyde.Co enzyme, thiamine pyrophosphate (TPP) and co factor Zn++ necessory for this, reaction ., Decarboxylation, 2CH3-CO-COOH ------------------------------------2CH3-CHO + CO2 ↑, [PA], Pyruvate Decarboxylase +TPP + Zn++ [Acetylaldehyde], 3. Reduction of Acetalaldehyde to ethyl alcohol (2H5OH):, Acetylaldehyde undergoes reduction with the help of NADH2 and there, is formation of ethyl alcohol., Reduction, 2CH3-CHO + 2NADH2------------------------------2C2H5OH+2 NAD, [Acetylaldehyde ], Dehydrogenase, [Ethyl alcohol], Summary:, Glycolysis, Decarboxylation, Reduction, Glucose---------------- PA----------------Acetalaldehyde-----------2C2H5OH, Fermentation: Anaerobic oxidation reduction process in which organic, compounds/respiratory substrate like glucose are broken down into, simple compounds with activity of micro-organisms., Fermentation is similar to anaerobic respiration but it is extra, or intra cellular., 4. Types:, 1. Alcoholic fermentation:, 2. Lactic acid fermentation:, , 1. Alcoholic fermentation:, Definition: The fermentation in which sucrose (molasses) converted into, glucose and glucose is converted into alcohol by the activities of, microbes (Yeast) is called as alcoholic fermentation., Substrate: Glucose, In many cases molasses used as substrate for alcoholic fermentation., Micro-organisms: Saccharomyces cervicae, , Mechanism:, 1. Hydrolysis (Conversion of sucrose into glucose) : Sucrose, undergoes hydrolysis and and conveted into glucose., Hydrolysis, C12H22O11 + H2O --------------------- C6H12O6 + C6H12O6, Sucrose, Glucose +Glucose, 16 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 2. Glycolysis (Conversion of glucose to PA) : Glucose undergoes, glycolysis and two molecules of PA formed. Sucrose Glucose +Glucose, Glycolysis, Glucose------------------------2PA., 3. Decarboxylation(Conversion of PA to acetaldehyde) : The PA, undergoes decarboxylation the presence of enzyme decarboxylase and, there is formation of acetylaldehyde., Decarboxylation, PA------------------------------ Acetylaldehyde + CO2 ↑, Decarboxylase, 4. Reduction of acetaldehyde to ethyl alcohol: Acetylaldehyde, undergoes reduction with the help of NADH2 in the presence of enzyme, alcohol dehydrogenase and there is formation of ethyl alcohol., Reduction, Acetylaldehyde + NADH2----------------------2C2H5OH+ NAD, Alcohol, Dehydrogenase, 5. Overall equation:, Yeast, C6H12O6----------------------------2C2H5OH+2 CO2 +2ATP, Zymase, 6. Summary:, Glucose --------PA------acetalaldehyde-------Ethyl alcohol, from above equation it is clear that, in alcoholic fermentation,, glucose undergoes fermentation with the help of yeast and in the, presence of zymase enzyme to form 2 molecules of C2H5OH,2, molecules CO2 and 2 molecules of ATP, , 2. Lactic acid fermentation:, 1. Definition: The process of fermentation in which lactose is converted, into lactic acid by the action of enzymes produced by lactic acid, fermenting bacteria., 2. Micro-organisms/Lactic acid bacteria: The bacteria which convert, lactose into lactic acid and causes souring of milk is called as lactic acid, bacteria., Examples: 1. Lactobacillus bulgaricus, 2. Streptococcus lactis, 3. Bacillus subtitis, 4. Acromobacteror lacticum, , 3. Mechanism:, 1. Hydrolysis (Convesrion of lactose to glucose and Galactose) :, lactose undergoes hydrolysis and converted into glucose and galactose., Hydrolysis, Lactose + H2O ------------------- Glucose +Galactose, 2. Glycolysis/Degradation (Conversion of glucose to Pyruvate) :, Glucose undergoes glycolysis and 2 molecules of PA are formed., Glycolysis, Glucose -----------------------PA, Carboxylation process is absent., 17 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , 3. Reduction of PA to lactic acid: PA acts as ultimate acceptor and it is, reduced to lactic acid by using NADH2, PA+ NADH2-------------------------- 2CH3CHOH-COOH+NAD, [Lactic acid], 4. Overall equation:, Lactic acid bacteria, C6H12O6------------------------------------------C12H22O11 +2ATP, Lactic acid dehydrogenase, o From above equation ,it is clear that after hydrolysis glucose undergoes, glycolysis to form PA .The PA reduced to lactic acid with the help of, lactic acid bacteria with the help of enzyme lactic acid dehydrogenase, 5. Summary:, Hydrolysis, Glycolysis, Reduction, Lactose ---------------Glucose --------------PA---------------------Lactic, acid, Points, 1.Substarate used, 2.Micro-organisms, 3.Enzymes used, 4.Release of CO2, 5.Ultimate H2, acceptor, 6. Overall reaction, , 7.Summary, reaction, 8.Uses, , Alcoholic, fermentation, Glucose, Yeast, Zymase, , Lactic acid, fermentation, Lactose, Lactic acid bacteria, Lactic acid, dehydrogenase, Absent, PA, , Present, Acetylaldehyde, C6H12O6--2C2H5OH+2 CO2, +2ATP, Glucose ---PA-----------acetalaldehyde--Ethyl alcohol, , C6H12O6------2CH3CHOH-COOH +2ATP, , Commercial, production, of alcohol, , Commercial production of, fermented dairy products, , Lactose ----Glucose ----PA---------Lactic acid, , Significance of Fermentation :, 1. Manufacturing of alcohol:, 2. Manufacturing of antibiotics:Antibiotics are secondary metabolities., Anaerobic fermentation, Specific microbes, Antibiotics, Released in fermentor, 3. Manufacturing of vitamins:, Anaerobic/Aerobic fermentation, Specific, Vitamins, Autolysis, Released in, Microbes intracellular process, of microbes, fermentor, 18 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , 4., 5., 6., 7., 8., 9., , BIOLOGY LECTURE NOTES, , XI SCIENCE, , Manufacturing of hormones, enzymes and glycerol., Preparation of fermented dairy products:, Curing of tea and tobacco leaves, Curdling of milk and Ripening of cream., Production of alcoholic beverages., Tanning of leather, , Exchange of gases in plants :, o Stomata and Lenticels: Plants do not have specialized organs for, respiration. Stomata and lenticels helps in gaseous exchange., o Root, stem and leaves : respire at very low rates as compared to, animals, o Germinating seeds and floral buds: respire at comparatively higher, rates., o Exchange of gases takes place during photosynthesis. Leaves are well, adopted for exchange of gases., o Leaves: In leaf, each living cell is located quite close to surface of plants, and contains stomata., o Stem: Living cells are beneath the bark and bark contains lenticels, o Loose packaging of Parenchymatous cells in stem and root provides, interconnected network of air spaces which fascinated gaseous exchange., , , Respiratory Quotient/Ratio: The ratio of volume of CO2, evolved to the volume of O2 consumed in respiration .RQ depends on, respiratory substrate., 1. CHO: RQ of CHO is 1 (Complete oxidation), 6CO2, RQ= ------------- = 1, 6 O2, 2. Fat: RQ is 0.7, C51H98O6+ 145O2 -------------102 CO2 + 98 H2O + ATP ( Energy), Tripalmitin, 102 CO2, RQ= ------------- = 0.7, 145 O2, 3. Protein: RQ is 0.9, 131 CO2, RQ= ------------- = 0.9, 145 O2, 4. Anaerobic Respiration: RQ is always affinity ( CO2 evolved without, taking O2), C6H12O6----------------------2C2H5OH+2 CO2 +2ATP, 2CO2, RQ= ------------- = Infinity, Zero O2, 19 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE
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MAURYA SCIENCE ACADEMY, , BIOLOGY LECTURE NOTES, , XI SCIENCE, , Respiration is Amphibolic pathway:, Fat, , Lipase, Glycerol, DHAP, , Respiratory substrate, , Degradation, , Protease, , Degradation, , Amino acids, , + Fatty acids, Lipase, , Protein, , Degradation, , Protease, , Degradation, , PGAL, , Acetyl co.A, , Pyruvate, , Acetyl co.A, , Acetyl co.A, , OR, , o Respiration is amphibolic pathway because during breakdown of, substrates, respiratory intermediate forms which helps in synthesis as, well as breakdown of proteins, fats, fatty acids and glycerol., o Respiratory intermediates forms the links during synthesis or, breakdown or Glycolysis and Kreb’s cycle provides precursors for the, many biosynthetic pathways., o Respiratory intermediates [Carboxylic acids] produced during Kreb’s, cycles serves as precursors of many amino acids. Amino acids are, building blocks for proteins., , Significance of Respiration:, 1. Release of energy: For biosynthesis of cellular material (CHO,, Proteins, Lipids, Vitamins ), 2. Synthesis of ATP and Providing carbon for photosynthesis:, 3. Production of alcohol: In anaerobic respiration, alcohol is produced, used in different medicines and product., 4. Preparation of organic acids: like lactic acid, acetic acid etc., 5. Providing starting material for synthesis of fats and proteins:, 6. Heat generation and Conversion of Food energy into unstable form:, 7. Maintaining O2 and CO2 balance., 8. Avoiding busting of cells : In respiration energy is form step by step, which avoids, 9. Acts as source of energy for cell division, growth, repairs, replacement, of worm out parts, movements and locomotion., 10., Intermediates of Kreb's cycle used as building blocks for, synthesis of other complex compounds., 11., Fermentation used in dairies ,bakeries, distilleries, leather, industries and paper industries, 12., Commercial production of alcohol, organic acid, vitamins and, antibiotics., 13., Energy of respiration convert insoluble substances into soluble, substances, 20 RESPIRATION, , |, , SIGN OUT BY DR. VIRESH SHELKE