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NAVAS CHEEMADAN, , Biomolecule, Introduction, • The living organisms are made of different, types of compound, • The chemical analysis reveals that it is, composed of elements like C,H,O,, • A piece of non living matter also contains, same type of elements, • In fact the living things and non living, things are made up of same elements, • However the relative abundance of, Carbon, hydrogen is higher in the living, organism than in non living matter, , How to analyze chemical composition?, Analysis of Organic elements and compounds in, the living tissue, •, , Take any living tissue (a vegetable or a piece, of liver, etc.) and grind it in Trichloroacetic, acid (Cl3CCOOH) using a mortar and a pestle., • We obtain a thick slurry. If we were to strain, this through a cheesecloth or cotton we, would obtain two fractions., a)The filtrate or, the acid-soluble pool, (micromolecule/biomolecule ),, b) The retentate or the acid-insoluble fraction, (Biomacromolecule )., a)Acid soluble pool, Scientists have found thousands of, organic compounds in the acid-soluble pool., There is one feature common to all those, compounds found in the acid soluble pool. They, have molecular weights ranging from 18 to, around 800 daltons (Da) approximately., SOHSS-AREEKODE/2021, , SOHSS-Areekode, , Micromolecules have molecular weight less than, 1000 Da., b) Acid insoluble pool, The acid insoluble fraction,, has only four types of organic compounds i.e.,, • Proteins,, • Nucleic acids,, • Polysaccharides and, • Lipids., • But the molecular weights of lipids do not, exceed 800 Da, come under acid insoluble, fraction. Because Cell membrane and other, membranes are broken into pieces during, the experiment , and form vesicles which are, not water soluble. Therefore, these, membrane fragments in the form of vesicles, get separated along with the acid insoluble, pool and hence in the macromolecular, fraction. Therefore lipids are not strictly, macromolecule., • The acid insoluble fraction has molecular, weight greater than 10000 Da., , Analysis of inorganic elements and compounds, in the living tissue, All the carbon compounds that we, get from living tissues can be called, ‘biomolecules’. However, living organisms have, also got inorganic elements and compounds in, them. A slightly different but destructive, experiment has to be done. One weighs a small, amount of a living tissue (say a leaf or liver and, this is called wet weight) and dry it. All the water,, evaporates. The remaining material gives dry, weight. Now if the tissue is fully burnt, all the, carbon compounds are oxidised to gaseous form, (CO2, water vapour) and are removed. What is, remaining is called ‘ash’. This ash contains, inorganic elements (like calcium, magnesium, etc). Inorganic compounds like sulphate,, phosphate, etc., are also seen in the acidsoluble fraction., , [email protected]

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NAVAS CHEEMADAN, , SOHSS-Areekode, , •, •, , •, The acid soluble pool represents roughly, the, cytoplasmic, composition., The, macromolecules from cytoplasm and organelles, become the acid insoluble fraction. Together, they represent the entire chemical composition, of living tissues or organism., , •, •, , Biomolecules, i.e., chemical compounds found in, living organisms are of two types. One, those, which have molecular weights less than one, thousand dalton and are usually referred to as, micromolecules or simply biomolecules while, those which are found in the acid insoluble, fraction are called macromolecules or, biomacromolecules., , •, , This breaking and making is through chemical, reactions constantly occurring in living, organisms., Together all these chemical reactions are, called metabolism. (Ie: The sum total of all, chemical reactions taking place in a living, organism is called metabolism ), Majority of these metabolic reactions are, always linked to some other reactions. This, series of linked reactions is called metabolic, pathways (So a multistep chemical reactions,, when each of the step is catalysed by the, same enzyme complex or different enzyme is, called a metabolic pathway.), These metabolic pathways are similar to, automobile traffic in a city., These pathways are either linear or circular., These pathways crisscross each other, i.e.,, there are traffic junctions. Flow of, metabolites through metabolic pathway has a, definite rate and direction like automobile, traffic., Another feature of these metabolic reactions, is that every chemical reaction is a catalysed, reactions and it is catalysed by enzymes., Eg: 1. In Glycolysis, glucose becomes Pyruvic, acid through ten different enzymes catalysed, metabolic reactions. But under normal, aerobic condtions pyruvic acid is formed., Eg :2 .In yeast, during fermentation, the same, pathway leads to the production of ethanol., Eg: 3. In our skeletal muscle, under anaerobic, condtions, lactic acid is formed, , Metabolism, The chemical reactions taking place in a, living organism is called metabolism., Metabolic pathways include 2 processes., a)Catabolism :, It is the breakdown process. This process, lead to the release of energy, Eg: When glucose is degraded to lactic acid in, our skeletal muscle , energy is liberated, which stored in the form of chemical bonds., When needed this bond energy is utilized, , Turnover, •, •, , One of the greatest discoveries ever made, was the observation that all these, biomolecules have a turn over., Biomoleculues are constantly being changed, into some other biomolecules and also made, from some other biomolecules. This is called, turn over., , SOHSS-AREEKODE/2021, , •, , This metabolic pathway from glucose to lactic, acid which occurs in 10 metabolic steps is called, glycolysis, , [email protected]

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NAVAS CHEEMADAN, , •, , b)Anabolism :, It is a synthetic phase. It requires energy, The energy currency in living systems is the, bond energy in a chemical called ATP, (Adenosine triphosphate ), , Primary and secondary metabolites, •, •, •, •, , •, , •, •, , Metabolites are organic compounds, constantly utilzed in various metabolic, activities in the cells., There are two types of metabolites, a)Primary metabolites:, It is essential to the growth of the cell., They are produced continuously during the, growth phase and are involved in primary, metabolic processes, Eg: proteins, nucleic acids, and, polysaccharides, b)Secondary metabolites :, They are the compounds which are derived, by pathways from primary metabolic routs,, and are not essential to sustain the life of, cells., These compounds do not have a continuous, production, Secondary metabolites are the end products, of primary metabolites such as alkaloids,, toxins, steroids, essential oils, lectins, drugs, etc, , SOHSS-Areekode, Essential to sustain life of not essential to, organism, sustain the life of cells., , They are produced, continuously during, the growth phase, , These compounds do, not have a continuous, production, , The living state, •, •, •, •, , The system at equilibrium cannot perform a, work. As living organisms work continuously,, they cannot afford to reach equilibrium., Hence the living state is a non equilibrium, steady state to be able to perform a work., Metabolism provides a mechanism for the, production of energy., Hence the living state and metabolism are, synonymous. Without metabolism there, cannot be a living state., • The blood concentration of glucose in, a normal healthy individual is, 4.2 mmol/L–6.1 mmol/L,, , Difference between primary metabolites, and secondary metabolites, Primary metabolites Secondary metabolites, They are involved in, normal growth, ,development and, reproduction, Examples include Amino, acids,sugars.., SOHSS-AREEKODE/2021, , They are not directly, involved in growth, development and, reproduction, Examples included, pigments,alkaloids…, [email protected]

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NAVAS CHEEMADAN, , •, •, , •, , 1. AMINO ACIDS, Amino acids are building blocks of, proteins., Amino acids are organic compounds, containing an amino group an acidic group, as substituents on the same carbon i.e., the, α carbon. Hence, they are called α-amino, acids. They are substituted methanes., There are four substituent groups, occupying the four valency positions. These, are hydrogen, carboxyl group, amino, group and a variable group designated, as R group., , SOHSS-Areekode, , Classification of amino acids, , a) Based on number of amino and carboxyl, groups, amino acids are classified into, i)Acidic amino acids, , Eg: Glutamic acid, Aspartic acid, , ii)Basic amino acids, , Eg: Lysine, , iii)Neutral aminoacids: Eg: Valine, , • There are aromatic amino acids, Eg: Tyrosine, Phenylalanine, Tryptophan, , •, , Based on the nature of R group there are, many amino acids. However, those which, occur in proteins are only of twenty types., , •, , Sulphur containing amino acid, Eg:Cysteine, , b)Based on the need to the human body ,, Amino acids are also classified into, a)Essential amino acids, b)Non essential amino acids, a)Essential amino acids, The amino acids that cannot be, synthesized in our body and it should be, provided through food is called essential amino, acids, b)Non essential amino acids, The amino acids that can be synthesized, in our body and no need to be supplied, through food is called non essential amino, acids, , ZWITTER ION, , A particular property of amino acids, is the ionizable nature of –NH2 and –COOH, groups. Hence in solutions of different pHs,, the structure of amino acids changes. At a, particular pH (Isoelctric point) of solution,, amino acids occur as a dipolar ions with +ve, SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , and –ve charge in the same molecule. They are, called Zwitter ions, , SOHSS-Areekode, , •, •, , 2. PROTEINS, • Proteins are polypeptides formed of, number of amino acids linked together by, means of Peptide bond., • Each protein is a polymer of amino acids, • Peptide bond is formed is formed when, the carboxyl (-COOH) group of one, amino acid reacts with the amino (-NH2), group of the next amino acid with the, elimination of a water (the process is, called dehydration), • Proteins are formed of number of different, kinds amino acids and hence proteins are, called heteropolymers., , •, •, , •, , Collagen is the most abundant protein in, animal world, Ribulose bisphosphate CarboxylaseOxygenase (RuBisCO) is the most, abundant protein in the whole of the, biosphere, , The first amino acid is also called as Nterminal amino acid. The last amino acid is, called the C-terminal amino acid., The primary structure of protein gives the, positional information of amino acids in a, protein., , b)Secondary structure of protein, • If the polypeptide is coiled to form of a helix, (similar to a revolving staircase) the, structure is called secondary structure of, protein., • In proteins, only right handed helices are, observed., c)Tertiary structure of protein, • If protein chain is also folded upon itself, like a hollow woolen ball, giving rise to the, tertiary structure. 3-dimensional view of a, protein., • Tertiary, structure, is, absolutely, necessary for the many biological, activities of proteins., d)Quaternary structure, If proteins are formed of more than one, polypeptide chain or subunits The manner in, which these individual folded polypeptides or, subunits are arranged with respect to each, other (e.g. linear string of spheres, spheres, arranged one upon each other in the form of a, cube or plate etc.) is the architecture of a, protein otherwise called the quaternary, structure of a protein., Eg: adult Haemoglobin consist of 4 subunits., It consist of 2α and 2β chain., , Biologists describe the protein structure at four, levels, , a)Primary structure of proteins, • Here the amino acids are arranged in a line ., • If a protein is imagined as a line, the left end, represented by the first amino acid and the, right end represented by the last amino acid., SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , SOHSS-Areekode, , •, , b)Glycerol, Another simple lipid is glycerol which is, trihydroxy propane, , c)Triglycerides (Fats and Oils), Many lipids have both glycerol and fatty, acids. Here the fatty acids are found esterified, with glycerol. They can be, i)Monoglycerides= 1 Fatty acids+ 1 Glycerol, ii)Diglycerides= 2 fatty acids+ 1glycerol, iii)Triglecerides=3 fatty acids+1 glycyerol, , •, •, , 3. LIPIDS, Lipids are water Insoluble, They could be simple fatty acids, Glycerol, and, may have both glycerol and fatty acids, , a)Fatty acids., A fatty acid has a carboxyl group attached, to an R group., , •, •, , The R group could be a methyl (–CH3), or, ethyl (–C2H5) or higher number of –CH2 groups, (1 carbon to 19 carbons)., For example, (a)Palmitic acid :, It has 16 carbons including carboxyl, carbon., , •, •, , These are also called fats and oils based on, melting point., Oils have lower melting point (e.g., gingely, oil) and hence remain as oil in winters., Fats have high melting point and occur in, solid form in room temperature., Some lipids have phosphorous and a, phosphorylated organic compound in them., These are phospholipids. They are found in, cell membrane., Eg: Lecithin, , (b)Arachidonic acid :, It has 20 carbon atoms including the carboxyl, carbon., • Fatty acids could be, i), Saturated-it is without double bond, ii), Unsaturated-It is with one or more, C=C double bonds)., , SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , •, •, , 4. Polysaccharide, Polysaccharides are long chains of sugars., They are threads containing different, monosaccharides, as, building, blocks., , SOHSS-Areekode, , •, •, •, •, , For example,, 1)cellulose is a polymeric polysaccharide, consisting of only one type of monosaccharide, i.e., glucose. Cellulose is a homopolymer. Plant, cell walls are made of cellulose, 2)Starch is a variant of this but present as a store, house of energy in plant tissues. It is also a, homopolymer of glucose., 3.Glycogen : Animals have another variant called, glycogen. It is also a homopolymer of glucose., 4.Inulin is a polymer of fructose., • In a polysaccharide chain (say glycogen),, the right end is called the reducing end, and the left end is called the non-reducing, end., Starch forms helical secondary structures. starch, can hold I2 molecules in the helical portion. The, starch-I2 is blue in colour. Cellulose does not, contain complex helices and hence cannot hold, I2., , •, , •, , •, •, •, , • There are more complex polysaccharides in, nature. They have as building blocks, aminosugars and chemically modified sugars (e.g.,, glucosamine, N-acetyl galactosamine, etc.)., 6)Exoskeletons of arthropods have a complex, polysaccharide called chitin. It is a homopolymer, , •, •, •, •, •, •, •, •, , SOHSS-AREEKODE/2021, , 5. Nucleic acids, Nucleic acids are macro molecule and found, in the acid insoluble part ., Nucleic acids act as the genetic material in all, organisms., Nucleic acids are polynucleotides (Formed of, number of nucleotides), A nucleotide has three chemically distinct, components., • A heterocyclic compound,, • A monosaccharide, • A phosphoric acid or phosphate., The heterocyclic compounds in nucleic acids are, the nitrogenous bases named adenine, guanine,, uracil, cytosine, and thymine. Adenine and, Guanine are substituted purines while the rest are, substituted pyrimidines. The skeletal heterocyclic, ring is called as purine and pyrimidine, respectively., The sugar found in polynucleotides is either ribose, (a monosaccharide pentose) or 2’ deoxyribose. A, nucleic acid containing deoxyribose is called, deoxyribonucleic acid (DNA) while that which, contains ribose is called ribonucleic acid (RNA), , Nucleic acids are of two types DNA and RNA, DNA (Deoxy ribonucleic acid ), DNA is formed of two polynucleotides. Each, poly nucleotides are formed of number of, nucleotides., A Single nucleotide is formed of nucleoside, and phosphate ., Eg: Adenylic acid, thymidylic acid, guanylic, acid, uridylic acid and cytidylic acid are, nucleotides, A nucleoside formed of sugar and nitrogen, base,, Eg:Adenosine, guanosine, thymidine, uridine, and cytidine are nucleosides., Sugar in DNA is deoxyribose and sugar in RNA, is ribose, Nitrogen bases are heterocyclic compounds.It, is of two types, purines (Double rings ) and, Pyramidine (Single ring)., Purines include Adenine, Guanine,, Pyramidine include Uracil, Cytosine and, Thymine, Nitrogen bases in DNA are Adenine, guanine,, thymine, Cytosine, Nitrogen bases in RNA is Adenine, guanine,, uracil ,Cytosine, [email protected]

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NAVAS CHEEMADAN, , •, •, , •, , There are two hydrogen bonds between A, and T and three hydrogen bonds between G, and C., At each step of ascent, the strand turns 36°., One full turn of the helical strand would, involve ten steps or ten base pairs.The pitch, would be 34Å. The rise per base pair would be, 3.4Å. This form of DNA with the above, mentioned salient features is called B-DNA., In a nucleic acid a phosphate moiety links the, 3’-carbon of one sugar of one nucleotide to, the 5’-carbon of the sugar of the succeeding, nucleotide. The bond between the phosphate, and hydroxyl group of sugar is an ester bond., As there is one such ester bond on either side,, it is called phosphodiester bond, , SOHSS-Areekode, , •, •, •, , Each step of ascent is represented by a pair of, bases. At each step of ascent, the strand turns, 36°., One full turn of the helical strand would, involve ten steps or ten base pairs. Attempt, drawing a line diagram., The pitch would be 34Å. The rise per base pair, would be 3.4Å. This form of DNA with the, above mentioned salient features is called, BDNA., , Diagram indicating secondary structure of DNA, , Watson crick Model of DNA, •, , •, •, •, •, •, , This model says that DNA exists as a, double helix. The two strands of, polynucleotides are antiparallel i.e., run in, the opposite direction., The backbone is formed by the, sugarphosphate-sugar chain., The nitrogen bases are projected more or, less perpendicular to this backbone but, face inside., A and G of one strand compulsorily base, pairs with T and C, respectively, on the, other strand., There are two hydrogen bonds between A, and T and three hydrogen bonds between, G and C., Each strand appears like a helical, staircase., , SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , SOHSS-Areekode, , Physical Process and Chemical Process, Physical Reaction, , Chemical Reaction, , A physical change, simply refers to a, change, in, shape, without breaking of, bonds., , when bonds are broken, and new bonds are, formed, during, transformation, this will, be called a chemical, reaction`, Example: ice melts into Example:, water, or when water Ba(OH)2 + H2SO4 →, becomes a vapour, BaSO4 + 2H2O, , •, , •, •, •, , •, , Rate of a physical or chemical process, Rate of a physical or chemical process refers, to the amount of product formed per unit, time. It can be expressed as, , A general rule of thumb is that rate doubles, or decreases by half for every 10°C change in, either direction., Catalysed reactions proceed at rates vastly, higher than that of uncatalysed ones., When enzyme catalysed reactions are, observed, the rate would be vastly higher, than the same but uncatalysed reaction., For example, , In the absence of any enzyme this reaction is, very slow, with about 200 molecules of, H2CO3 being formed in an hour. However, by, using the enzyme present within the, cytoplasm called carbonic anhydrase, the, reaction speeds dramatically with about, 600,000 molecules being formed every, second. The enzyme has accelerated the, reaction rate by about 10 million times. The, power of enzymes is incredible indeed!, , SOHSS-AREEKODE/2021, , 6. Enzymes, •, , Enzymes are biological catalyst capable of, promoting biochemical reactions within a, living system., • Almost all enzymes are proteins., • But some nucleic acids behave like enzymes, are called Ribozymes (Non Protein enzyme), Substrate : Substance upon which the enzyme, act., Active site : it is the substrate binding site of an, enzyme, End product : the substance obtained at the end, of enzymatic reactions, • Enzymes are damaged at high temperature, (Above 40 c), • Some enzymes isolated from organism who, normally, live, under, extreme, high, temperature (like hot vents ) are stable and, retain their catalytic power even at high, temperature (80-90 c)., • Thermal stability is thus an important quality, of such enzymes isolated from thermophilic, organisms ., Nature of Enzyme action, Each enzyme (E) has a substrate (S), binding site in its molecule so that a highly, reactive enzyme-substrate complex (ES) is, produced. This complex is short-lived and, dissociates into its product(s) P., The catalytic cycle of an enzyme, action can be described in the following steps:, 1. First, the substrate binds to the active site of, the enzyme, fitting into the active site., 2. The binding of the substrate induces the, enzyme to alter its shape, fitting more tightly, around the substrate., 3. The active site of the enzyme, now in close, proximity of the substrate breaks the, chemical bonds of the substrate and the new, enzyme- product complex is formed., 4. The enzyme releases the products of the, reaction and the free enzyme is ready to bind, to another molecule of the substrate and run, through the catalytic cycle once again, , [email protected]

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NAVAS CHEEMADAN, , SOHSS-Areekode, , •, , Enzymes perform a very important task by, lowering the activation energy of the reaction, (the energy put in for the reaction to begin)., This lowering of energy allows the biological, reaction to proceed very quickly at a very low, temperature which is bearable by living, organisms. Enzymes eventually bring down, this energy barrier making the transition of ‘S’, to ‘P’ more easy., , Factors affecting enzyme activity, Concept of activation energy, , •, •, •, •, , •, •, , In the above graph the y-axis represents the, potential energy content., The x-axis represents the progression of the, structural transformation or states through, the ‘transition state’., Here we can see two things. The energy level, difference between S and P., If ‘P’ is at a lower level than ‘S’, the reaction, is an exothermic reaction. One need not, supply energy (by heating) in order to form, the product. However, whether it is an, exothermic or spontaneous reaction or an, endothermic or energy requiring reaction, the, ‘S’ has to go through a much higher energy, state or transition state., The difference in average energy content of, ‘S’ from that of this transition state is called, ‘activation energy’, Activation energy is defined as the minimum, amount of extra energy required by a, reacting molecule to get converted into, product., , SOHSS-AREEKODE/2021, , The activity of an enzyme can be affected, by a change in the conditions which can alter, the tertiary structure of the protein., • These include temperature, pH, change in, substrate concentration or binding of specific, chemicals that regulate its activity, a)Temperature and pH, , •, , Enzymes generally function in a narrow, range of temperature and pH., • Each enzyme shows its highest activity at a, particular temperature and pH called the, optimum temperature and optimum pH., • Activity declines both below and above the, optimum value., • Low temperature preserves the enzyme in a, temporarily inactive state whereas high, temperature destroys enzymatic activity, because proteins are denatured by heat., b) Concentration of Substrate, , [email protected]

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NAVAS CHEEMADAN, , •, , •, , With the increase in substrate concentration,, the velocity of the enzymatic reaction rises at, first. The reaction ultimately reaches a, maximum velocity (Vmax) which is not, exceeded by any further rise in concentration, of the substrate., This is because the enzyme molecules are, fewer than the substrate molecules and after, saturation of these molecules, there are no, free enzyme molecules to bind with the, additional substrate molecules, , c) Enzyme Inhibition, The substance that shutoff the enzyme, activities are called inhibitors and the process is, called enzyme inhibition. When the inhibitor, closely resembles the substrate in its molecular, structure and inhibits the activity of the enzyme,, it is known as competitive inhibitor. Due to its, close structural similarity with the substrate, the, inhibitor competes with the substrate for the, substrate binding site of the enzyme (Active site)., Consequently, the substrate cannot bind and as a, result, the enzyme action declines,, e.g., Inhibition of succinic dehydrogenase by, malonate which closely resembles the, substrate succinate in structure., • Such competitive inhibitors are often used in, the control of bacterial pathogens., , Classification and Nomenclature of, Enzymes, Thousands of enzymes have been, discovered, isolated and studied. Most of these, enzymes have been classified into different, groups based on the type of reactions they, catalyse. Enzymes are divided into 6 classes each, with 4-13 subclasses and named accordingly by a, four-digit number., 1.Oxidoreductases/dehydrogenases:, Enzymes, which catalyse oxidoreduction between two, substrates S and S’ e.g.,, S reduced + S’ oxidised → S oxidised + S’ reduced., 2.Transferases: Enzymes catalysing a transfer of a, group, G (other than hydrogen) between a pair of, substrate S and S’ e.g.,, S - G + S’ → S + S’ - G, , SOHSS-AREEKODE/2021, , SOHSS-Areekode, , 3.Hydrolases: Enzymes catalysing hydrolysis of, ester, ether, peptide, glycosidic, C-C, C-halide or, P-N bonds., 4.Lyases: Enzymes that catalyse removal of, groups from substrates by mechanisms other, than hydrolysis leaving double bonds., , 5.Isomerases: Includes all enzymes catalysing, inter-conversion of optical, geometric or, positional isomers., 6.Ligases: Enzymes catalysing the linking together, of 2 compounds, e.g., enzymes which catalyse, joining of C-O, C-S, C-N, P-O etc. bonds., , Co-factors, The protein Part of an enzyme is called, apoenzyme. The non protein part of en enzyme is, called cofactor.Three kinds of cofactors may be, identified: prosthetic groups, co-enzymes and, metal ions., a)Prosthetic groups:, They are organic compounds and are, distinguished from other cofactors in that they, are tightly bound to the apoenzyme., Example: in peroxidase and catalase, which, catalyze the breakdown of hydrogen peroxide to, water and oxygen, haem is the prosthetic group, and it is a part of the active site of the enzyme., b)Co-enzymes :, They are also organic compounds but their, association with the apoenzyme is only transient,, usually occurring during the course of catalysis., The essential chemical components of many, coenzymes are vitamins, e.g., coenzyme, nicotinamide adenine dinucleotide (NAD) and, NADP contain the vitamin niacin., c)Metal ions :, A number of enzymes require metal ions for their, activity which form coordination bonds with side, chains at the active site and at the same time, form one or more cordination bonds with the, substrate,, e.g., zinc is a cofactor for the proteolytic enzyme, carboxypeptidase., • Catalytic activity is lost when the co-factor, is removed from the enzyme, , [email protected]

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NAVAS CHEEMADAN, , Previous year questions, 1. Observe the graph and comment, , SOHSS-Areekode, 8. ........... is the most abundant protein in the animal, world., (HSE March 2019)(1), 9. Observe the diagram A and B given below, , (HSE-Sept-2021)(1), , 2. Write the structure of, , (HSE-Sept-2021)(2), , (a) Alanine (b) Glycine, , 3. Non-protein constituents called co-factors are, bound to the enzyme, to make it catalytically, active., (HSE-Sept-2021)(3), (a) Name the protein part of the enzyme., (b) Mention any two kinds of co-factors with, examples., (c) What happens to the catalytic activity of, enzyme, when the co-factor is removed ?, , 4. Observe the following equation, , a)Explain the catalytic cycle of the enzyme on, the basis of above equation, b)Write any 2 factors affecting enzyme, activity ?, (HSE-Dec-2020)(3), 5. Which among the following is a primary, metabolite ?, (HSE-March-2020)(1), , 6. When substrate concentration increases, the, velocity of enzymatic reaction increases at, first. After attaining a maximum velocity, it, cannot be exceeded by further addition of, substrates. Why ?, (HSE-March-2020)(2), 7. Match the following, (HSE-July-2019)(3), , a)What is A and B’, b)Mention the other two levels of protein, structure ?, (HSE March 2019)(2), 10. General formula of amino acid is given below, (HSE-Model-2019)(3), , (a) Prepare the amino acide serine using this, formula, (b) Proteins carry out many functionsin living, organisms, Iist any four., (c) Give one word, (i) The nucleic acid that behave like, enzymes, (ii) The organic compound tightly, bound to the apoenzyme., (iii) The, non-protein, organic, compound that are not tightly, bound to the apoenzyme, (iv) The protein part of the enzyme, 11. Observe the graph given below, (HSE-Aug-2018)(3), , a) Identify the graph., b) Mention the role of Enzyme in this, process., SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , 12. The molecular structure of 2 amino acids are, given below Name them.(HSE-March-2018)(2), , 13. a)Complete the diagrammatic representation, showing the nature of enzyme action :, (HSE-March-2018)(3), , b) List out any two factors affecting enzyme, activity., c)Based on the reaction formulae given, below, identify the classes of the enzymes., , 14. a) Effect of change in concentration of, substrate on enzyme activity is graphically, represented' After reaching a maximum, velocity (Vmax)" the reaction is not exceeded, by any further rise in concentration of, substrate' Explain", b) Mention any 2 other factors that affect, enzyme activity ?, (HSE-Model-2018)(3), , SOHSS-Areekode, , In a proteins aminoacids are linked by, ….(a)…In, a, polysacharides, individual, monosacharides are linked by…….(b)….., 16. Identify the wrong statement from the, following and correct it, (HSE-July-2017)(1), a)Lipds are not strictly macromolecule, b)Cellulose is not a polysaccharide, 17. Examples of 2 enzymatic reactions A and B, are given. Identify the class of enzyme in A, , (HSE-July-2017)(2), , and B, , A) S reduced + S’ oxidised → S oxidised + S’ reduced., , (S,S’- Substrate ), B) S - G + S’ → S + S’ – G, (S,S’- substrate,G-Group), , OR, 18. “ Proteins is a heteropolymer not a, homopolymer “ . Substantiate the statement, ?, (HSE-July-2017)(2), 19. Identify the given biomolecule that comes, under fat, (HSE-sept-2016)(1), , 20. a)Name the biomacromolecule (Polymer) in, which peptide bond is present ?, b)Name the bond present between, phosphate and hydroxy group of sugar in, nucleic acid ?, , (HSE-sept-2016)(2), , 21. Metabolites are organic compunds constantly, utilzed in various metaolic activities in the, cells (HSE-March-2016)(2), a)What are the two types of metabolites in, the cells?, 15. Fill in the blanks suitably (HSE-Model-2018)(2), SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , b)Give an example for each type of, metabolites?, 22. Enzymes are biocatalyst which regulate, various biochemical reaction, Illustrate the following reaction, (HSE-March-2016)(2), , the following sequence, with approprite words, (HSE September-2015)(1), Amino acids:………(a)…….bond:protein, ………(b)………: glycosidic bond :, polysacharide, 24. Based on the graph given below,, explain the effect of concentration of, substrate on enzyme activity., (HSE September-2015)(2), , SOHSS-Areekode, , 26. Analyze the graph showing the activity, , of an enzyme, influenced by, temperature, (HSE march-2015)(2), , 23. Compelete, , a)What is meant by optimum, temperature?, b)why does enzyme activity declines at, too low and at too high temperature?, 5. a. Why are proteins heteropolymers?, b.Identify the proteins from the given, list of iomacromolecule and write its, functions, (Cellulose,starch,antibody, inulin), c.Identify the type of protein structure, of a and b, (HSE August-2014)(3), , 25. Identify the protein structures, (a) and, , (B) from the following figure, (HSE March-2015)(1), 6. Symbolic presntation of a functional, enzyme is given below, (HSE August-2014)(3), , SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , a.Write one difference between, cofactor and apoenzyme?, b.name the different types of cofactor, c.what is the cofactor for the enzyme ,, carboxypeptidase, 7. Name the chemical bond formed, between the following, (HSE March-2014)(1), a. Amino acids in a protein moleucle, b. Sugar and phosphate in a nucleic, acid, 8. Distinguish between cofactor and, coenzyme with an example for each?, (HSE March-2014)(2), 9. Oserve the graph and answer the, following (HSE-SEPTEMBER-2013)(3), , a.Find out the role of enzyme?, b.Mention any two factors that, influence the activity of an enzyme and, state their influences?, 10., , SOHSS-Areekode, , b. Name the bond produced when, another compound of the same, category combine with this?, c. If a number of such molecule, bonded together , what will e the, resultant molecule ?, 11.Oserve the graph shoing the activity of, an enzyme influenced y pH, (HSE march-2013)(2), , a. Name the possible enzyme involved, in this reaction?, b. Where is its site of action, c. Mention any other factor which, affects this enzyme, d. Name another, similar enzyme, acting on the same sustrate, 12.Fill in the blanks, (HSE September-2012)(1), Carbohydrate : sugar, Proteins:………….., 13.Analyse the graph showing the activity, of salivary amylase, (HSE September-2012)(1), , (HSE MARCH-2013)(1.5), a. Identify this compound?, SOHSS-AREEKODE/2021, , [email protected]

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NAVAS CHEEMADAN, , a.Which, is, the, optimum, temperature for salivary amylase, from the graph?, b.Why the activity declines below, the optimum value ?, 14.Non protein constituent called cofactor, are bound to the enzyme to make the, enzyme catalytically activity, (HSE March-2011)(3), a.Name the protein portion of the, enzyme, b.What happens to the catalytic, activity when the cofactor is removed, from the enzyme?, c.Mention any two kinds of cofactor, with examples?, 15.Observe the graph, , SOHSS-Areekode, , c.If a chemical substance closely, resembling to that of a substrate is, introduced into a reaction system,, what will be the consequences?, Sustantiate, 16.Fill in the blanks coloumns with the, correct terms/sentence, (HSE march-2009) (2), A, B, …………(1)………., Catalyse, oxiod, reduction, between, 2, sustrate, Transferase, …………(2)……….., Lyases, Catalyse hydrolysis, of ester, glycosidic, bond, ………(3)………., Catalyse, inter, conversion, of, opical isomers, Ligase, ………(4)………., , (HSE-March 2010), a.What is meant by ‘Vmax’ value?, b.Why is ‘Vmax’ not exceeded by any, further rise in the substrate, concentration, SOHSS-AREEKODE/2021, , [email protected]