Lecture 9 - Carbohydrates (PDF)

Lecture 9 Carbohydrate Carbohydrates or saccharides are polyhydroxy Aldehydes or ketones, or substances that yield such compounds on hydrolysis. The general formula of carbohydrate is Cn( H2O)n but this is not unique to carbohydrates for example from Aldehydes (C...

Lecture 9 Carbohydrate Carbohydrates or saccharides are polyhydroxy Aldehydes or ketones, or substances that yield such compounds on hydrolysis. The general formula of carbohydrate is Cn( H2O)n but this is not unique to carbohydrates for example from Aldehydes (CH2O) and acetic acid (C2H4O2) are certainly not carbohydrates. Carbohydrates contain nitrogen and sulfer as well as C, H, O. Despite these problems, the name carbohydrate is used today carbohydrate are also called sugars or saccharides because of sweet taste of simpler members of the family. Carbohydrate are classified into three main classes. Most plants contain (60 – 90)% carbohydrate whereas most animal contain small amount. Carbohydrate Monosaccharide Disaccharide Polysaccharide 1-Monosaccharide: Cannot hydrolysis to the simple sugar and Called simple saccharides molecules also can be classified according to the a- Number of carbon atoms in the chain. They found commonly in human include the following: b- The nature of carbonyl group for example hexosis C6H12O 6 c- Can be classified into two type 1- Aldohexose Contain Aldehydes group such as glucose, galactose and mannose 2- Ketoses Contain ketones group such as fructose Glucose is a major energy source for the humane body, derived from the Breakdown of carbohydrates obtained from daily diet and regulated through the Process of glycogenolysis (breakdown of body stored glycogen),and glycogenosis. When glucose Level is rises above the than normal range the condition referred to as Hyperglycemia Glucose is filter through glomerular filtration and then completely reabsorbed Through proximal tubules In normal conditions, the ability of proximal tubules for Reabsorbed glucose is limited up to the glucose level in blood is 160-180 mg \dl of Blood. Glucose is the most important carbohydrate;  most dietary carbohydrate is absorbed into the bloodstream as glucose, and other sugars are converted to glucose in the liver.  Glucose is the major metabolic fuel of mammals  It is the precursor for synthesis of all the other carbohydrates in the body, including : ✓ glycogen for storage; ✓ Ribose and deoxyribose in nucleic acids; ✓ Galactose in lactose of milk, ✓ In glycolipids, ✓ And in combination with protein in glycoproteins and proteoglycans. 2- Disaccharides Composed of two molecules of simple sugar linked by glycosidic linkages such as Lactose, Maltose and sucrose. 3- Polysaccharides They are polymers of glucose units linked together by glycosidic linkages such as starch, dextrin's, glycogen and cellulose. Polysaccharides are sometimes classified as hexosans or pentosans, depending on the identity of the constituent monosaccharides some types of polysaccharide. Also we can classified carbohydrate as 1- Reducing sugars They are contain free Aldehydes or ketones groups that are capable of reducing on oxidizing agent. Maltose that is composed of two molecules of glucose Lactose that is composed of molecules glucose and galactose Sucrose that is composed of molecules glucose and fructose. Maltose + H2O H+ glucose + glucose Lactose + H2o H+ glucose + galactose Fructose + H2O H+ glucose + fructose These carbohydrate gives ( +ve) test with Tollen, Fehling and Bendict. All monosaccharide's is reducing sugars except sucrose. 2- Non reducing sugar Lack of free Aldehydes or ketones group e.g sucrose which is composed of one molecule of α – glucose and one molecule of β – fructose linked together by β – 1 – 2 – glycosidic linkage. Sucrose cannot give ( + ve) with last reagent. 3- Oligo saccharides are condensation products which is composed (3 – 12) unites of monosaccharides. Most are not digested by human enzymes. Poly saccharides H2O + H+ Oligosaccharides H2O + H+ Monosaccharide's ( C12H20O10)n n H2O n( C12H22O11) n H2O 2n (C6H12O6) Polysaccharide disaccharide monosaccharide starch maltose glucose Glycogen, also known as animal starch, is structurally similar to amylopectin, containing both Alpha(1→4) and (1→6) glycosidic linkages branch points. Glycogen is even more highly branched, with branches occurring every 8 to 12 glucose units. Glycogen is abundant in the liver and muscles; on hydrolysis it forms D-glucose, which maintains normal blood sugar level and provides energy. Starch Is a polymer consisting of D-glucose units. Starches (and other glucose polymers) are usually insoluble in water because of the high molecular weight. and they contain large numbers of OH groups, some starches can form thick colloidal dispersions when heated in water (e.g., flour or starch used as a thickening agent in gravies or sauces). There are two forms of starch: amylase and amylopectin. Cellulose Is a polymer consisting of long, unbranched chains of D-glucose connected by alpha (1→4) glycosidic linkages; it may contain from 300 to 3000 glucose units in one molecule. Most animals lack the enzymes needed to digest ,cellulose, but it does provide roughage (dietary fiber) to stimulate contraction of the intestines and help pass food through the digestive system.  Lecture 10 Amino acid It is compounds that are considered basic molecules to form large vital molecules, basic component of amino acid that consider the backbone of its structure are a carboxyl group, an amine group, alpha hydrogen group, and R group. These groups consider the basic factors that must be present in the composition of the amino acid in order to enter the protein synthesis. Amino acids are classified into non polar amino acid. Amino acids contain a hydroxyl group. Amino acids contain an rings compounds. Amino acids that contain sulfur groups. Under normal condition, a person's intake of nitrogen in food is equal to the nitrogen lost by excretion; that is, there is a nitrogen balance. Sometimes an organism can have a positive nitrogen balance. In this case, nitrogen intake is greater than loss of nitrogen. This occurs whenever tissue is being synthesized, for example, during periods of growth. A negative nitrogen balance( nitrogen intake less than loss of nitrogen) occurs during fasting or with a diet that lacks or is deficient in protein. Certain organisms are capable of synthesizing all 20 amino acids from water, carbon dioxide, and nitrates from soil. Humans and higher animal  The twenty common amino acids are often referred to using three-letter  change includes. The deficiency in any impairs protein synthesis and whole-body homeostasis, leading to serious health problems, including 1- muscle wasting, 2- little growth, 3- compromised immune function, 4- skin diseases, and 5 - metabolic and neurological disorders. Peptide bond Short chain of amino acids linked by peptide bonds, where these amino acids are linked to each other by subtracting water molecules. Peptides play an essential role in fundamental physiological processes and are necessary for many biochemical processes. A peptide is a short string of 2 to 49 amino acids, Most Common And Important Peptides. Oxytocin is a cyclic hormone consisting of 9 amino acids that works to reduce uterine tissues, as well as is present in blood vessels. Vasopressin is a cyclic hormone consisting of 9 amino acids. Works on increasing blood pressure. Glutathione is a triple peptide consisting of glutamine, glycine, and cysteine. It is an abnormal bonding process. It is one of the important peptides. It is one of the important antioxidants. It is always found in the double form, s-s bond. Bradykinin is a peptide consisting of 9 amino acids and is responsible for expansion of blood vessels, which causes low blood pressure.  Lecture 12 Protein Proteins are polymers compound of covalently linked amino acids that form polypeptide chains ; first of these polypeptides can fold into a regularly repeating structures. In the studies of protein structure we have four structures: 1- Primary structure of protein, its linear sequence of amino acid from N- terminal to C – terminal Ex NH2CHRCO( NHCHRCO) n NHCHRCOOH N – terminal unite C – terminal unite n = 12 – 1000 2- Secondary structure These are three types of secondary structures a- α – Helix and b – β – pleated sheet c- reverse turns 3- Tertiary structure Is the overall folding and binding of a single polypeptide chain. 4- Quaternary structure If the protein formed from more than one polypeptide chain each chain will be called a subunit the arrangement of these subunit called quaternary structure. Proteins synthesis The cell contains a set of structures within the nucleus. The cell contains the genome. It is divided into 23 pairs of chromosomes. Each chromosome contains a long chain of DNA wrapped around a protein called histones. To manufacture a specific protein, DNA polymerase sticks to the beginning of the genome strand during the process of moving along the DNA, which determines the arrangement of this protein with the free bases of the nucleus, and then DNA is cloned by the transcription process. Before this strand is used as a template for the manufacture of protein, it must be processed and ensure that there are no mutations, then it goes outside the nucleus into the cytoplasm and is linked to ribosomes for this messenger, and then an amino acid chain is formed based on the template taken from the DNA, and the amino acids are arranged with each other by tRNA. Proteins metabolism Digestion of proteins begins in the stomach. When protein-rich foods enter the stomach, they are greeted with a mixture of the enzyme pepsin and hydrochloric acid, which produces a pH that denatures the proteins. Pepsin breaks down proteins into smaller polypeptides and their constituent amino acids. When the mixture enters the small intestine, the small intestine secretes digestive hormones, which stimulate the digestive processes to further break down proteins. Secret in; also stimulates the pancreas to release sodium bicarbonate.  The pancreas releases most digestive enzymes, including the proteases trypsin, chymotrypsin, and elastase, which aid in the digestion of protein. Together, all these enzymes break down complex proteins into smaller individual amino acids, which are then transported across the intestinal mucosa to be used to create new proteins, or to be converted into fats or acetyl-CoA and used in the Krebs cycle. The hydrolysis of proteins to tree amino acids is the result of the combined action of the proteolytic enzymes in the gastrointestinal tract. Once formed, the amino acids are absorbed into the blood and created to the liver. Here the metabolism of amino acid take place. There is one common feature; all amino acids are degraded into two parts. One part contains α – amino groups. The other part contains compounds that have carbon skeleton of the orginal amino acids. The nitrogen containing compounds are finally degraded to urea, and the carbon skeletons are finally degraded to carbon dioxid and water. These paths are it turns out that the carbon containing parts of amino acids are degraded to only five compounds that are part of citric acid cycle. Water:  The most abundant chemical compound in living system 60-70% of our body is water.  2/3 of the total body water is intracellular.  The rest is interstitial fluid of 25% is in the blood plasma.  Acts as a solvent for the substances we need such as Na+ ,K+ , glucose , adinosine tri phosphate(ATP) and proteins.  The body controls both the volume and the PH of water.  Maintain a constant environment for the cells called homeostasis ( the same environment ).  Regulates the body temperature.  A reactant and product in many chemical reactions that take place in the living system.  Transporting load and oxygen to the cell and carrying away wastes.  A medium for movement of molecules into and out of cellular compartments.  Important to the structure and function of bio molecules. Buffers: A buffer is one which resists change in pH when small quantities of an acid or a base are added to it. 1. Acidic buffer : is one which has a pH less than 7. Acidic buffer solutions are made from a weak acid and one of its salts-often a sodium salt. Example : a mixture of ethnoic acid and sodium ethanoate. 2. Basic buffer : is one which has a pH greater than 7. Alkaline buffer solutions are made from a weak base and one of its salts. Example : a mixture of ammonia solution and ammonium chloride. How do buffer solutions work?  Acid buffer : example: Ethnoic acid & sodium ethanoate. Ethnoic acid is a weak acid and the position of equilibrium will be to the left. CH3COOHaq ↔ CHECOO-aq +H+ Adding CH3COONa adds more CH3COO- ions. According to the chatelaines principle ( if a system at equilibrium is disturbed by changing the conditions , the position of equilibrium will be shifted to counteract the change) , the position of equilibrium will be shifted further to the left. Adding an acid ti this buffer , the buffer removes most of the new hydrogen ions by combination of H+ ions with CH3COO- ions to form CH3COOH. Since CH3COOH is a weak acid most of new H+ ions removed by this way. CH3COO-aq + H+aq ↔ CH3COOHaq since most of the new H+ ions are removed , the PH will not change very much. Adding an alkali to this buffer , the OH- will react with CH3COOH and position of equilibrium will be shifted to right. CH3COOHaq + OH-aq↔ CH3COO-aq + H2O  Alkaline buffer solutions : consist of weak base and its conjugate acid. Example : NH+4 & NH4CL. NH3aq+H2O ↔ NH4+aq + OH- Adding NH4CL to this adds more NH4+ ions. According to Le chatelier,s principle , the equilibrium will be shifted to the left. Adding an acid , the H + ions of the acid are removed by reacting with ammonia and the equilibrium will be shifted to right. Also the H+ ions are removed by reacting with OH- form from the reaction of NH3 with H2O. NH3 + H2O ↔ NH+4 + OH- Adding alkali to this buffer, the OH- of the alkali are removed by reaction with NH+4 ions according to the following reaction. NH+4 + OH- ↔ NH3 + H2O Chemical equilibrium : A chemical reaction is in a state of equilibrium when the amount of products lost per second by the forward reaction exactly equals the amounts of product lost per second by the reverse reaction.the quantities of products & reactants present at equilibrium are related to each other by equilibrium constant expression. 3H2 + N2 ↔ 2NH3 K = [ NH3]2 / [H2]2 [N2] K= equilibrium constant When the equilibrium constant is greater than 102 , more of the reactants have been converted to products. Thus the products are favored in an equilibrium reaction whose k > 102. When the equilibrium constant is less than 10-2 , only a very small amount of product is formed. Therefore , the reactants are favored in an equilibrium reaction whose K is < 10-2. If the K is between 10-2 - 102 neither product nor reactant is greatly favored. The le - chatelier principle  “ if a system at equilibrium is disturbed by an applied stress , the system changes in such way that this external stress is minimized “ Many examples of this principle are found in living system. 1. Oxygen needed by the body is carried in the blood stream to the cells as oxyhemoglobin Hemoglobin + 4O2 ↔ oxyhemoglobin 2. Glucose - 1 – phosphate enzyme G- 6 –P K = [ G – 6 - P ] / [ G – 1 P] = 2 The important equilibrium in aqueous solute is the one involved in the ionization of water. 2H2O ↔ H3O+ + OH- The tendency of H2O to ionize is very small. The concentration of H+ is 1×10-7 M. the concentration of OH- is 1×10-7 M. only one of every 550×106 water molecules is ionized K = [ H3O+] [ OH-] / [H2O]2 K [H2O]2 = K- = [ H3O+] [OH-] The ionization of H2O is simply written as H2 O H+ + OH - [ H3O +] = [ H +] K = KW = [ H+ ] [ OH-] = [ 1x10 -7] [ 1 x10-7] = 1x 10 -14 [ H+ ] = [ OH- ] Neutral solution [ H +] > [ OH - ] Acidic solution [ H + ] < [ OH - ] Basic solution Henderson – Hasselbach equation pH = pKa + log [ salt] / [ acid] pH = pKa ( maximum buffer capacity) Control of pH in body fluids: In the human body the blood plasma has a normal PH of 7.4. If the PH fall below 7 or rise above 7.8 the results would be fatal. The PH of the body is controlled by buffers systems which are very effective in protecting this fluid from large changes in PH. If 1ml of 10M HCL were added to 1L of un buffered normal saline (0.15M NACL) at 7 pH ,the pH would fall to 2. But if 1ml of 10M HCL is added to 1L of blood at PH 7.4, the PH will drop to only 7.2 1 L of ( 0.15 M NaCL pH = 7) + 1 ml of (10 M HCL) ↔ pH = 2 1 L of blood (pH 7.4) + 1 ml of ( 10 M HCL) ↔ pH = 7.2 1) The major buffer system in blood is carbonic acid - bicarbonate system. H2CO3 ↔HCO -3 + H+ adding a strong acid to the system will increase the concentration of H+ , shifting the reaction to the left and forming more carbonic acid. H2CO3→HCO-3 + H+ but carbonic acid is unstable and will decomposes to CO2 and H2O. H2CO3 → CO2 + H2O the carbon dioxide can be removed from the blood and exhaled by lungs. Various factors can cause abnormal increase in acid levels in the blood. such factors are hypoventilation , ingestion of excess acids , excess loss of bicarbonate or deceased excretion of H+ through kidney failure. All of these conditions will cause an increase in H+ levels in the blood and a decrease in the concentration of basic components such as HCO-3. when the PH of blood drops to 7.1 the condition is known as acidosis ( either respiratory system or metabolic , if the origin is other than respiratory , the body has many ways to restore the blood PH to normal)  It can expel the excess CO2 formed from H2CO3 through an increase in the rate of breathing.  It can increase the excretion of H+ and retention of H2CO3 by kidneys resulting in acidic urine. The bicarbonate buffer system also protects against an addition of strong base to the system. A base will react with the H+ ions to produce water, decreasing the H+ ions concentration in the system. This will drive the reaction to the right H2CO3 ↔ HCO-3 + H+ An increase in base in blood can occur in cases of hyperventilation ,excessive ingestion of basic substances such as antacids. The pH of blood can increase to 7.8 resulting in a condition known as alkalosis. the body can return the pH to normal by many ways  Decrease in expulsion of CO2 by the lungs.  An increase excretion of HCO-3 by kidneys , resulting in an alkaline urine Bicarbonate Buffer  The principal extracellular buffer, comprising carbonic acid (the proton donor) and bicarbonate (the proton acceptor). It functions in the same way as other conjugate acid base pairs. However, there are important differences: 1. The base constituent, bicarbonate (HCO3 -) is regulated by kidneys. 2. The acid component (H2CO3) is regulated by pulmonary ventilation. Thus, bicarbonate buffer is subject to regulation by kidneys and lungs. The acid component of this buffer (also called respiratory component) is generated from dissolved carbon dioxide [CO2(d)] and water, by the reaction shown below. The reaction is catalyzed by the enzyme carbonic anhydras The dissolved carbon dioxide in blood circulation is in equilibrium with the gaseous carbon dioxide [CO 2(g)] in the air space of the lungs. As a result, concentration of carbonic acid is ultimately dependent on the partial pressure of carbon dioxide in the gas phase. Carbonic acid can dissociate to yield bicarbonate. Thus, reversible equilibrium exist between the gaseous carbon dioxide in the lungs and the bicarbonate ions in blood plasma, as shown below: Action of the bicarbonate buffer involves these equilibrium. For instance, when an acid is added to blood, concentration of H rises. The latter is taken up by HCO3 – resulting in the rise of concentration of carbonic acid (Step 1). This causes the Step 2 to go forward, and the concentration of carbon dioxide (d) in the blood rises. This in turn results in an increase in the pressure of carbon dioxide in the gas phase in the lungs (Step 3), and the extra carbon dioxide is exhaled through increased rate of breathing. Reverse series of reactions occur when an alkali (OH) is added. It is taken up by carbonic acid to form HCO3 -. Concentration of carbonic acid falls momentarily, but is quickly replenished from large pool of gaseous carbon dioxide. Rate of breathing decreases under these circumstances so that the carbon dioxide is retained and dissolved in water to form carbonic acid. Bicarbonate buffer is highly effective: Bicarbonate buffer system is an effective physiological buffer because of its equilibration with a large reserve of gaseous carbon dioxide in the air space of the lungs. Since pK’ of carbonic acid is 6.1, the bicarbonate buffer should be most effective at or around pH of 6.1 (i.e. 6.1 1) as a buffer is most effective when pH equals pK’. However, bicarbonate buffer is highly effective at the physiological pH of 7.4 also because of its equilibration with gaseous carbon dioxide. Carbonic anhydrase is the principle enzyme that catalyzes generation of HCO3 -. Decreased activity of this enzyme, therefore, results in decreased plasma bicarbonate concentration. Consequently, the ratio of bicarbonate to carbonic acid (normally 20) tends to fall, resulting in a fall of pH 2) Another buffer active mainly with the cell is the phosphate buffer system. H2PO-4↔ HPO-24 Adding strong acid will drive the reaction to the left , increasing the concentration of H2PO-4. Adding strong base will drive the reaction to right as H+ reads with base to form H2O.the kidney remove any excess of HPO-24 and H2PO-4 from the body  ‫اذكرونا بالخير‬ Second semester general questions.‫هي بوليمرات مركبة من أحماض أمينية مرتبطة تساهميًا وتشكل سالسل متعددة الببتيد‬ 1- ------------- are polymers compound of covalently linked amino acids that form polypeptide chains. a- protein b- lipid c- carbohydrate d- vitamin.‫ هيكل‬-------------------- ‫يتم تصنيف البروتني إلى‬ 2- Protein are classified into-------------------- structure. a- 2 b- 4 c- 6 d- 8 ‫ تسلسله الخطي من األحماض األمينية من‬،‫من البروتني‬ 3----------------------- of protein, its linear sequence of amino acid from N- terminal to C – terminal a- Quaternary structure b- tertiary structure c- secondary structure d- primary structure ‫التركيب األساسي للبروتني يحتوي على‬ 4- Primary structure of protein contain------------------------. a- 5 – 100 a.a b- 10 – 500 a.a c- 12 – 1000 a.a d- 24 – 1000 a.a ‫تصنيف البنية الثانوية للبروتني إلى‬ 5- Secondary structure of protein are classified into -------------------- a- only α – helix b- only pleated sheet c- only reverse turns d- all of them ‫تسلسل بنية البروتني األولية لسلسلة‬ 6- Primary protein structure sequence of chain of ------------------ a- a.as b- carbohydrate c- vitamin d- lipid ‫ هيكل الترابط الهيدروجيني للعمود الفقري الببتيد يتسبب في طي األحماض األمينية لنمط متكرر‬------------------ ‫ثانوي‬ 7- Secondary ------------------ structure hydrogen bonding of peptide back bone causes the aminoacids tofold a repeating pattern------------ a- Oligo saccharides b- protein c- disaccharides d- lipid.‫هو الطي والربط الشامل لسلسلة بولي ببتيد واحدة‬ 8- -------------------- Is the overall folding and binding of a single polypeptide chain. a- α – helix b- plated sheet c- tertiary structure d- reverse turn  ‫البروتني املتكون من أكثر من سلسلة بولي ببتيد كل سلسلة سوف يطلق عليها وحدة‬.‫فرعية وترتيب هذه الوحدات الفرعية يسمى البنية الرباعية‬ 9- If the protein formed from more than one polypeptide chain each chain will be called a subunit the arrangement of these subunit called quaternary structure. ----------------------. a- β – pleated sheet b- reverse turns c- poly saccharides d- non of them ‫تحتوي الخلية على مجموعة من التراكيب داخل النواة‬ 10- -------------------- the cell contains a set of structures within the nucleus a- Protein syntheses b- glycogen syntheses c- poly saccharides d- non of them ‫ وهي مقسمة إلى‬.‫تحتوي الخلية على الجينوم‬ 11- The cell contains the genome. It is divided into ------------ pairs of chromosomes. a- 18 b- 23 c- 24 d- 25.‫ ملفوفة حول بروتني يسمى الهستونات‬---------- ‫يحتوي كل كروموسوم على سلسلة طويلة من‬ 12 - Each chromosome contains a long chain of---------- wrapped around a protein called histones. a- RNA b- mRNA c- DNA d- nucleus ‫يتم ترتيب األحماض األمينية مع بعضها البعض حسب‬ 13- The amino acids are arranged with each other by ------------. a- DNA b- mRNA c- DNA d- tRNA.‫يبدأ هضم البروتينات في املعدة‬ 14- --------------- Digestion of proteins begins in the stomach. a- Protein metabolism b- carbohydrate metabolism c- lipid metabolism c- all of them ‫اإلنزيم املوجود في املعدة هو‬ 15- The enzyme present in stomach is -------------. a- amylase b- pepsin c- catalase d- non of them ‫الحمض املوجود في املعدة هو‬ 16- The acid present in stomach is --------------. a – HNO3 b- H2SO4 c- HCl d- H2CO3 ‫الرقم الهيدروجيني للمعدة‬ 17- The pH of stomach is ----------------------. a- 7 -8 b- 8 – 10 c- 10 – 12 d- 1 -3.‫يكسر البروتينات إلى عديدات ببتيدات أصغر تشكل أحماض أمينية‬ 18- ----------------- breaks down proteins into smaller polypeptides and their constituent amino acids. a- Pepsin b- amylase c- catalase d- urease ‫ تفرز األمعاء الدقيقة الجهاز الهضمي‬،‫عندما يدخل الخليط إلى األمعاء الدقيقة‬ 19- When the mixture enters the small intestine, the small intestine secretes digestive ---------------------. a- Vit. D b- hormones c- carbohydrate d- cortisol ‫كما تحفز األمعاء الدقيقة البنكرياس على إفراز‬ 20- Small intestine also stimulates the pancreas to release --------------. a- HCl b- CH3COOH c- NaHCO3 d- NaOH ‫املنتج النهائي لتحلل األحماض األمينية هو‬ 21- The end product of amino acid degradation is ------------------- a- Carbonic acid b- uric acid c- creatinin d- urea ‫ بما في ذلك‬،‫يفرز البنكرياس معظم اإلنزيمات الهاضمة‬ 22- The pancreas releases most digestive enzymes, including the------. a- Only protease b- only trypsin c- only elestase d- all of them ‫ يتم تحويل األحماض إلى دهون أو‬.‫األمينية‬ 23- Amino acid are converted into fats or ---------------------. a- Acetyl Co A b- isocitrate c- α – ketoglutarate d- oxaloacetate ‫يتم امتصاص األحماض األمينية في الدم وتكوينها‬ 24- The amino acids are absorbed into the blood and created to the----------------. a- Heart b- liver c- stomach d- kidney ‫تتحلل الهياكل العظمية الكربونية أخيرًا إلى‬ 25- Carbon skeletons are finally degraded to----------------------. a- urea b- urea and water c- CO2 and H2O d- CO2, H2O and energy ‫هي مركبات تعتبر جزيئات أساسية لتكوين جزيئات حيوية كبيرة‬ 26- ------------------- It is compounds that are considered basic molecules to form large vital molecules. a- Amino acid b- carbohydrate c- lipid d- non of them. ‫ الذي يعتبر العمود الفقري لبنيته‬----------- ‫املكون األساسي‬ 27- Basic component of ----------- that consider the backbone of its structure. a- Lipid b- sugar c- vitamin d- amino acid. ‫مكون الحمض األميني الذي يعتبر العمود الفقري لبنيته‬ 28- The component of amino acid that consider the backbone of its structure. a- carboxyl group b- amino group c- α – hydrogen group d- all of them  ‫التركيب البسيط للحمض األميني هو‬ 29- The simple structure of amino acid is ----------------------. a- NH4+ - CH2R COO- b- NH3+- CHR COO- c- NH2+ CH3- COO- d- - NH+ CH2 CH- COO- ‫العوامل األساسية التي يجب أن تتواجد في تركيب الحمض األميني حتى يدخل في تركيب البروتني‬ 30- The basic factors that must be present in the composition of the amino acid in order to enter the protein synthesis ---------------------. a- α- amino group and α – carbon group b- R- group and α- hydrogen group c- α – hydrogen group and carboxyl group d- all of them ‫حمض أميني غير قطبي يحتوي على‬ 31- Non polar amino acid contain a ---------------------. a- Hydroxyl group b- rings compound c- sulfur group d- all of them ‫ على شحنة هي‬a.a + ve ‫يحتوي‬ 32- The a.a contain +ve charge are ----------------------. a- Only lysine b- only arginin c- only histidin d- all of them ‫أ غير القطبية تحتوي على حلقات هي‬.‫أ‬ 33- The non polar a.a contain rings are--------------------. a- Only proline b- only tryptophan c- only phnyl alanin d- all of them ‫ يكون تناول الشخص للنيتروجني في الطعام مساوياً للنيتروجني املفقود بنسبة‬،‫في الظروف العادية‬ 34- Under normal condition, a person's intake of nitrogen in food is equal to the nitrogen lost by ----------------. a- Excretion b- absorption c- adsorption d- non of them ‫ يكون تناول النيتروجني‬،‫ في هذه الحالة‬.‫في بعض األحيان يمكن أن يكون لدى الكائن الحي توازن نيتروجيني إيجابي‬ 35- Sometimes an organism can have a positive nitrogen balance. In this case, nitrogen intake is -----------------. a- Low than loss of nitrogen b- greater than loss of nitrogen c- adequate of nitrogen d- non of them ‫بعض الكائنات الحية قادرة على تصنيع جميع األحماض األمينية العشرين‬ 36- Certain organisms are capable of synthesizing all 20 amino acids ------------. a- only from water b- only from carbon dioxide c- only fron nitrate from soil d- all of them ‫ الشحنة‬ve - ‫أ‬.‫تحتوي على القطبية أ‬ 37- Polar a.a contain – ve charge are -------------------------. a- Aspartic acid and glutamic acid b- tyrosin and serin  c- theronin and asparagen d- non of them ‫غالبًا ما يشار إلى األحماض األمينية العشرين الشائعة باستخدام‬ 38- The twenty common amino acids are often referred to using ------. a- One – letter b- two letter c- three letter d- all of them ‫تحسني تنظيم املسار األيضي األساسي‬ 39- Regulating essential metabolic pathway improve-------------------. a- Health b- survival c- growth all of them ‫األحماض األمينية ضرورية لنمو وتطور وإصالح‬ 40- Amino acids are essential for growth, development and repair of -------------. a- Only muscle b- help produce collagen c- elasticity d- all of them ‫تساعد على توليد الطاقة من‬.‫أ‬ 41- A.a help to generate energy from --------------------. a- Carbohydrate b- lipid c- vitamin d- non of them --- ‫األحماض األمينية تساعد على التنظيم‬ 42- Amino acid help toregulate ---------------------------. a- Insulin resistance b- insulin secretion c- body mass index d- vitamin D -‫األحماض األمينية ضرورية للحياة الطبيعية‬ 43- Amino acid are necessary for normal-----------------------. a- Heart function b- kidney function c- brain function d- liver function ‫األحماض األمينية تستخدم لتخليق‬ 44- Amino acid are used for synthesis of ------------------------. a- Glycogen b- protein c- lipid d- collagen ‫ بما في ذلك‬،‫ مما يؤدي إلى مشاكل صحية خطيرة‬،‫نقصها أي يضعف تخليق البروتني والجسم كله التوازن‬ 45- The deficiency in any impairs protein synthesis and whole-body homeostasis, leading to serious health problems, including -----------. a- Muscle wasting b- little growth c- skin disease d- all of them ‫ روابط‬---------- ‫سلسلة قصيرة من األحماض األمينية مرتبطة بواسطة‬ 46- Short chain of amino acids linked by ---------- bonds a- Peptide b- covalent c- ionic d- hydrogen ‫ الجزيئات‬---- ------ ‫ترتبط األحماض األمينية ببعضها البعض عن طريق طرح‬ 47- amino acids are linked to each other by subtracting ---------- molecules. a- Hydroxyl group b- water c- carboxyl group d- side chain ،‫ األحماض األمينية‬------------- ‫الببتيد عبارة عن سلسلة قصيرة من‬ 48- A peptide is a short string of ------------- amino acids, a- 2 to 20 b- 2 to 30 c- 2 to 40 d- 2 to 60.‫ أحماض أمينية يعمل على تقليص أنسجة الرحم‬9 ‫هو هرمون دوري يتكون من‬ 49- ------------------- is a cyclic hormone consisting of 9 amino acids that works to reduce uterine tissues. a- Vasopressin b- glutathione c- oxytocin d- bradykinin ‫ يعمل على زيادة ضغط الدم‬.‫ أحماض أمينية‬9 ‫هو هرمون دوري يتكون من‬ 50- -------------------- is a cyclic hormone consisting of 9 amino acids. Works on increasing blood pressure. a- Oxytocin b- glucagon c- bradykinin d- vasopressin.‫ والجليسني والسيستني‬----------- ‫هو ببتيد ثالثي يتكون من‬ 51- Is a triple peptide consisting of -----------, glycine, and cysteine. a- Glutathion b- oxytocin c- growth hormone d- cortisol.‫ أحماض أمينية وهو املسؤول عن توسيع األوعية الدموية مما يسبب انخفاض ضغط الدم‬9 ‫هو ببتيد يتكون من‬ 52----------------------- is a peptide consisting of 9 amino acids and is responsible for expansion of blood vessels, which causes low blood pressure. a- FSH b- prolactine c- bradykinin d- testosterone ‫الكربوهيدرات أو السكريات هي بولي هيدروكسي‬ 53- Carbohydrates or saccharides are polyhydroxy-------------------------. a- Only aldehyde b- only keton c- aldehyde and keton d- non of them ‫الصيغة العامة للكربوهيدرات هي‬ 54- The general formula of carbohydrate is -----------------------. a- Cn( H2O)n b- C2n(H2O)2n c- C2(H2O)2n d- Cn(H2O)2 ‫ هي‬C2H4O2 ‫صيغة‬ 55- The formula of C2H4O2 is --------------. A Carbohydrate b- acetic acid c- propanol d- fructose - ‫تحتوي الكربوهيدرات على‬ 56- Carbohydrate contain ------------------. a- C and H b- C and O c- C and N d- all of them ‫كربوهيدرات تصنف إلى‬ 57- Carbohydrate are classified into ----------------------. a- monosaccharide b- disaccharide c- polysaccharide d- all of them.‫ كربوهيدرات‬------------- ‫تحتوي معظم النباتات على‬ 58- Most plants contain ------------- carbohydrate. a- (60 90)% b- ( 50 -60)% c- ( 90 – 120)% d- non of them.‫ الكربوهيدرات‬------------------- ‫تحتوي معظم الحيوانات على‬ 59- Most animal contain ------------------- carbohydrate. a- Large amount b- small amount c- mild amount d- moderate amount  ‫السكريات األحادية املصنفة حسب‬ 60- Monosaccharide classified according to the-------------------. a- Number of hydroge atom b- number of oxygen atom c- number of carbon atom d- number of sulfer atom ‫مصدر رئيسي للطاقة في جسم اإلنسان‬ 61- --------------------is a major energy source for the humane body. a- Maltose b- sucrose c- glucose d- lactose - ‫عندما يرتفع مستوى الجلوكوز فوق املعدل الطبيعي تسمى الحالة‬ 62- When glucose Level is rises above the than normal range the condition referred to as ------------------. a- Hypertension b- hypotension c- hypoglycemia d- hyperglycemia ‫تتم تصفية الجلوكوز من خالل الترشيح الكبيبي ثم يعاد امتصاصه بالكامل من خالل‬ 63- Glucose is filter through glomerular filtration and then completely reabsorbed through------------------. a- Proximal tubule b- distil tubule c- loop of henal d- non of them ‫ والسكريات األخرى تتحول إلى‬--------------- ‫يتم امتصاص معظم الكربوهيدرات الغذائية في مجرى الدم حيث أن‬ 64- Most dietary carbohydrate is absorbed into the bloodstream as ----------------.‫جلوكوز في الكبد‬ and other sugars are converted to glucose in the liver. a- Fructose b- glucose c- maltose d- ribose.‫ للتخزين‬------------ ‫ بما في ذلك‬،‫الجلوكوز هو املادة األولية لتخليق جميع الكربوهيدرات األخرى في الجسم‬ 65-Glucose the precursor for synthesis of all the other carbohydrates in the body, including ------------ for storage. a- Glucagon b- glycogen c- glycolipid d-glycoprotein ‫هو الوقود األيضي الرئيسي للثدييات‬ 66- ---------------- is the major metabolic fuel of mammels a- Ribose b- galctose c- glucose d- lactose ‫السكر املوجود في الكتوز الحليب‬ 67- The sugar in the lactose of milk--------------------. a- sucrose b- fructose c- maltose d- galactose.‫يتم دمجه مع البروتني في البروتيوغليكان‬ 68- ---------------- is combination with protein in glycoproteins and proteoglycans. a- glucose b- lactose c- mannose d- ribose.‫يتكون من جزيئني من السكر البسيط املرتبطني بروابط جليكوسيدية‬ 69- --------------- Composed of two molecules of simple sugar linked by glycosidic linkages. a- Monosaccharides b- disaccharides c- poly saccharides d- non of them.‫تحتوي على مجموعات ألدهيدات أو كيتونات حرة قادرة على تقليل العامل املؤكسد‬ 70- ----------------- are contain free Aldehydes or ketones groups that are capable of reducing on oxidizing agent. a- Poly saccharides b- disaccharides c- oligosaccharides d- reducing sugar ‫في التحلل املائي يتكون املالتوز من جزيئني من‬ 71- In hydrolysis maltose is composed of two molecules of ------------. a- glucose b- galactose c- fructose d- ribose ‫في التحلل املائي للسكريات الثنائية الالكتوز التي تتكون من جزيئات‬ 72- In the hydrolysis of disaccharides lactose that is composed of two molecules --------------------. a- Glucose and fructose b- glucose and galactose c- glucose and mannose d- glucose and ribose.‫ ال يتم هضم معظمها بواسطة اإلنزيمات البشرية‬.‫( وحدة من السكريات األحادية‬12 – 3) ‫هي نواتج التكثيف التي تتكون من‬ 73- -----------------------are condensation products which is composed (3 – 12) unites of monosaccharides. Most are not digested by human enzymes. a- Non reducing sugar b- poly saccharides c- oligo saccharides d- monosaccharide ‫صيغة السكريات املتعددة هي‬ 74- The formula of poly saccharides are ------------------------. a- [C6H12O10]n b- [ C12 H20 O5]n c-[C12 H20O11]6 d- [C12H20O10]n ‫صيغة السكريات القليلة هي‬ 75- The formula of oligo saccharides are----------------------. a- [C12H22O11]n b- C12H20O10 c- C10H20O11 d- [C12H12O6]n - ‫صيغة السكريات األحادية هي‬ 76- The formula of monosaccharide is -----------------------. a- n[C6H10O10] b- 2n[C12H6O6] ‫منها‬ ‫ حيث توجد فروع في كل‬،‫بًا‬c- ‫تشع‬4n[C6H12O6] ‫ الجليكوجني أكثر‬d- 2n[C12H6O6] 77-. Glycogen is even more highly branched, with branches occurring every ------------------------. a- (4 – 12) G units b- (6 – 12)G units c- (8 – 12)G unts d- (6 – 8) G units 78- Glycogen is abundant in the liver and muscles; on hydrolysis it forms --------------which maintains normal blood sugar level and provides energy. a- α- glucose b- β- glucose c- L – glucose d- D- glucose ‫ مما يحافظ‬-------------- ‫ عند التحلل املائي يتكون‬.‫الجليكوجني متوفر بكثرة في الكبد والعضالت‬.‫على مستوى السكر الطبيعي في الدم ويوفر الطاقة‬  ‫ والتي عادة ما تكون غير قابلة للذوبان في املاء بسبب‬.‫ الجلوكوز‬-D ‫عبارة عن بوليمر يتكون من وحدات‬ ‫ وتحتوي على أعداد كبيرة من مجموعات‬.‫الوزن الجزيئي العالي‬ 79- ----------------------Is a polymer consisting of D-glucose units. Which are usually insoluble in water because of the high molecular weight. and they contain large numbers of OH groups, a- Starch b- glycogen c- cellulose d- oligosaccharide ‫ روابط جليكوسيدية‬--------------- ‫ الجلوكوز متصلة بواسطة ألفا‬-D ‫عبارة عن بوليمر يتكون من سالسل طويلة غير متفرعة من‬ 80- Is a polymer consisting of long, unbranched chains of D-glucose connected by alpha --------------- glycosidic linkages a- ( 1 2) b- ( 1 3) c- ( 1 4) d- (1 5).‫ وحدة جلوكوز في الجزيء الواحد‬3000 ‫ إلى‬300 ‫تحتوي على من‬ 81- ----------------contain from 300 to 3000 glucose units in one molecule. a- Glycogen b- cellulose c- starch d- oligo saccharides ‫ في جسمنا هو املاء‬------------ ‫املركب الكيميائي األكثر وفرة في النظام الحي‬ 82- The most abundant chemical compound in living system ------------ of our body is water. a- (60 – 70)% b- ( 70 – 80)% c-(80 – 90)% d- ( 85 – 95)%.‫من إجمالي املاء في الجسم يكون داخل الخاليا‬ 83------------ of the total body water is intracellular. a- 1 / 3 b- 2 / 3 c- 3 / 4 d- 4 / 5.‫ املوجود في بالزما الدم‬------------ ‫والباقي هو السائل الخاللي‬ 84- The rest is interstitial fluid of ------------ is in the blood plasma. a- 10% b- 20% c- 25% d- 30%.‫( والبروتينات‬ATP) ‫يعمل كمذيب للمواد التي نحتاجها مثل الصوديوم والبوتاسيوم والجلوكوز واألدينوسني ثالثي الفوسفات‬ 85- ------------ Acts as a solvent for the substances we need such as Na+ ,K+ , glucose , adinosine tri phosphate(ATP) and proteins. a- H2CO3 b- NaHCO3 c- CH3COOH d- H2O.‫ للماء‬PH ‫ و‬----------- ‫يتحكم الجسم في‬ 86- The body controls both the ----------- and the PH of water. a- Volume b- density c- temperature d- all of them ‫ تسمى باالستتباب‬----------- ‫يحافظ املاء على بيئة ثابتة‬ 87- Water maintain a constant environment for the -----------called homeostasis a- Liver b- cell c- heart d- kidney ‫املاء ينظم الجسم‬ 88- Water regulates the body-------------------. a- Volume b- pH c- temperature d- weight.‫مادة متفاعلة وناتجة في العديد من التفاعالت الكيميائية التي تحدث في النظام الحي‬ 89- -----------a reactant and product in many chemical reactions that take place in the living system. a- Acid b- base c- salt d- water.‫ إلى الخلية وحمل الفضالت‬--------‫نقل املاء و‬ 90 – Water transporting load and --------- to the cell and carrying away wastes. a- Oxygen b- carbondioxid c- carbonmonoxid d- salt ‫مهم لبنية ووظيفة الجزيئات الحيوية‬ 91- --------------important to the structure and function of bio molecules. a- Acid b- base c- water d- buffer.‫هو الذي يقاوم التغير في الرقم الهيدروجيني عند إضافة كميات صغيرة من حمض أو قاعدة إليه‬ 92- A ----------- is one which resists change in pH when small quantities of an acid or a base are added to it. a- Plasma b- blood c- temperature d- buffer.7 ‫هو الذي درجة حموضةه أقل من‬ 93 - ------------ is one which has a pH less than 7. a- Acid buffer b- base buffer c- mixture d- non of them. ‫تتكون املحاليل من حمض ضعيف وأحد أمالحه‬ 94- ------------ solutions are made from a weak acid and one of its salts. a- Acid buffer b- alkaline buffer c- weak acid d- all of them. ‫ وسيكون موضع التوازن إلى اليسار‬------------ ‫الحمض العرقي‬ 95- Ethnoic acid is a ------------ and the position of equilibrium will be to the left. a- Salt b- strong acid c- weak acid d- all pf them. ‫ تتكون من قاعدة ضعيفة وحمض مرافق لها مثل‬: ‫املحاليل املنظمة القلوية‬ 96- Alkaline buffer solutions : consist of weak base and its conjugate acid such as. a- NaHCO3&H2SO3 b- Na2CO3&HNO3 c- Na2HPO4& HCl d- NH4 + &NH4Cl 97- 3H2 + N2 2NH3 a- k = [ NH3]2 / [H2]3 [N2] b- k = [ NH3]2 / [H2] [N2] c- - k = [ H2]3 / [NH3] [N2] d- - k = [ N2] / [H2] 3 [NH3] ‫يتم نقل األكسجني الذي يحتاجه الجسم مع مجرى الدم إلى الخاليا كما‬ 98- Oxygen needed by the body is carried in the blood stream to the cells as a- Dioxyhemoglubin b- trioxyhemoglobin c- oxyhemoglubin d- all of them --‫معادلة هندرسون – هاسيلباخ هي‬ 99- Henderson – Hasselbach equation is----------------. a- pH = pkb + log [acid] / [salt] b- pH = pKa + log [ salt] / [ acid] c- pH = pKa + log [ acid] / [ salt] d-- pH = pkb + log [salt] / [acid]  ‫ تتمتع بالزما الدم بدرجة حموضة طبيعية تبلغ‬،‫في جسم اإلنسان‬ 100- In the human body the blood plasma has a normal pH of ----- a- 6.8 b- 7 c- 7.2 d- 7.4 ‫النظام العازل الرئيسي في الدم هو‬ 101- The major buffer system in blood is --------------------------. a- NaHCO3 &NaOH b- Na2CO3& NaOH c- H2CO3 & NaHCO3 d- NH4Cl & H2CO3 ‫يمكن إزالة ثاني أكسيد الكربون من الدم وإخراجه عن طريق الزفير بواسطة‬ 102- The carbon dioxide can be removed from the blood and exhaled by --------------------- a- Kidney b- liver c- heart d- lungs ‫كما يحمي نظام البيكربونات العازلة أيضًا ضد اضافة… للنظام‬ 103- The bicarbonate buffer system also protects against an addition of ----------------- to the system. a- Strong base b- dilute base c- strong acid d-dilute acid --- ‫يمكن أن تحدث زيادة في القاعدة في الدم في حاالت‬ 104- An increase in base in blood can occur in cases of --------------. a- Hypoventilation b- hyperventilation c- hypotension d- hypertension ‫ البول‬..‫ عن طريق الكلى مما يؤدي إلى‬HCO3 ‫زيادة في طرح‬ 105- An increase excretion of HCO -3 by kidneys , resulting in an ----------------- urine a- Acid b- normal c- alkaline d- non of them --- ‫( ينظمها‬- HCO3) ‫املادة القاعدية البيكربونات‬ 106- The base constituent, bicarbonate (HCO3 -) is regulated by -------------------. a- Heart b- liver c- lungs d- kideys  Alkafeel University College of Health & Medical Techniques By Asst.L.Sarah Sattar Jabbar 1 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  are among the most abundant constituents of plants and animals. They serve as source of energy (sugars), and as stores of energy (starch and glycogen). They also form the major constituent (chitin) of the shells of crabs and lobsters, and the supporting tissue of plants (cellulose). Plants build up carbohydrate from CO2 and H2O by photosynthesis. Carbohydrates have the general formula CnH2nOn alkafeel.edu.iq [email protected]  Carbohydrates may be classified into 1- are often referred to as simple sugars (e.g., glucose) and cannot be hydrolyzed into simpler compounds.Monosaccharides can be subdivided based on the number of carbon (C) atoms. The following list shows the prefixes for numbers of carbons in a sugar. Aldehyde ketone Trioses C3H6O3 glyceraldehyde dihydroxyacetone Tetroses C4H8O4 erythrose erythrulose Pentoses C5H10O5 ribose ribulose Hexoses C6H12O6 glucose fructose 4 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  form when two monosaccharides join together by a dehydration reaction, also known as a condensation reaction or dehydration synthesis. In this process, the hydroxyl group of one monosaccharide combines with the hydrogen of another, releasing a molecule of water and forming a covalent bond known as a glycosidic linkage. Reducing sugar: A disaccharide in which the reducing sugar has a free hemiacetal unit serving as a reducing aldehyde group. Examples include maltose and cellobiose. Non-reducing Sugar: Disaccharides that do not have a free hemiacetal because they bond through an acetal linkage between their anomeric centers. Examples are sucrose and trehalose. 5 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  are compounds that yield 3 to 10 molecules of the same or different monosaccharides on hydrolysis. All the monosaccharides are joined through glycosidic linkage. are a chain of more than 10 carbohydrates joined together through glycosidic bond formation. They are ubiquitous and mainly involved in the structural or storage functions of organisms. They are also known as glycans. they are classified into two groups: 6 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Biological significance carbohydrates are generally available as an immediate energy source, whereas lipids act as a long-term energy resource and tend to be utilized at a slower rate. Glucose, the prevalent uncombined, circulating in the blood of higher animals, is essential to cell function. The proper regulation of glucose metabolism is of paramount importance to survival. 7 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Sources of glucose into blood 8 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021 Qualitative Analysis of Carbohydrates 9 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Materials:- sulphuric acid (conc.). α-naphthol (5% iin ethanol , prepare fresh ) sugar solution :- glucose, maltose, sucrose, starch, distilled water. Which carbohydrate gives a positive result with Molisch’s test? All carbohydrates (monosaccharides, disaccharides, and polysaccharides) pass the Molisch test. It is based on Sulphuric acid dehydrating the carbohydrate to produce an aldehyde, which condenses with two molecules of α-naphthol, resulting in the appearance of a purple ring at the interface. What is the negative result of Molisch test? The purple-coloured ring forms at the interface between the sulphuric acid and the test solution. Because the sulphuric acid is denser than the test solution, it remains above it. The lack of colour indicates a negative outcome. alkafeel.edu.iq [email protected]  THANK U 4 LISTENING 11 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Biochemistry//Determination of blood urea By Asst.L.Sara Sattar Jabbar lec.2 1 alkafeel.edu.iq [email protected]  The kidneys are one of the main organs of the excretory system. The excretory system is the organ responsible for eliminating metabolic waste.The kidneys are two fist-sized organs located on either side of the spine near the bottom of the rib cage Regulatory functions The kidneys regulate three essential and interrelated properties of the tissues water content acid-base balance, osmotic pressure in such a way as to maintain electrolyte and water equilibrium alkafeel.edu.iq [email protected] Urea is one of the end products of protein metabolism. Some of it is derived from food, and some from the breakdown of tissues. It is eliminated from the blood stream by the kidney, and passes out in the urine. In health, blood always contains some urea, the level varying between children between 1 and 17 years: 7 – 20 mg/dL. Adult women: 6 - 21 mg/dL. Adult men: 8 - 24 mg/dL. alkafeel.edu.iq [email protected]  Urea is one of the major end products of protein nitrogen metabolism. It is synthesized in liver from ammonia which is produced by amino acids deamination. The determination of serum urea nitrogen is an important index of kidney function. impaired renal function or increased tissue breakdown are associated with increased urea nitrogen levels alkafeel.edu.iq [email protected]  Disposal of urea, through the urine and this conversion is done in the liver through a series of reactions called the cycle Ornithine - cycle or The urea cycle alkafeel.edu.iq [email protected]  Urea Cycle 6 alkafeel.edu.iq [email protected]  Clinical significance blood urea: Increase in BUN = The value increase in kidney disease, shock, dehydration, diabetes, acute myocardial infarction. Decrease in BUN = The value decreases in liver failure, impaired absorption and overhydration (increased urinary outflow) 7 alkafeel.edu.iq [email protected]  Evaluation of Urea Concentration in The Sera Samples of Patients and Control Groups The Principle Urea is hydrolyzed by urease into ammonia and carbon dioxide, the generated ammonia reacts with alkaline hypochlorite and sodium salycilate in presence of sodium nitroprusside as coupling agent to yield a green chromophore. The intensity of the color formed is proportional to the concentration of urea in the sample. Absorbance is measured at 600 nm. Urease Urea +H2O 2NH3 +CO2 Nitroprusside/OH ¯ NH4 +Salycilate +NaClO Indophenol + NaCl Reagents Urease reagent (R1): 500 U/ mL Buffered Chromogen (R2): it is a mixture of phosphate buffer (20 mmol/L pH 6.9), EDTA (2 mmoI /L), sodium salycilate (60 mmoI/L) sodium nitroprusside (3.4 mmo/L). alkafeel.edu.iq [email protected]  The procedure The procedure of urea determination involved used of three tubes, sample (T), blank (B), and standard (S) tubes. The method involved the following steps: Additive Sample (T) Standard (S) Blank (B) Working reagent 1mL 1mL 1 mL Sample 10μL Standard 10 μL R3 1 mL 1 mL 1 mL Tubes were mixed and incubated for 5 minutes at 37 °C The absorbance of the tubes was read at 600 nm Calculations Abs. of T-B Urea Concentration (mg/dL) = × S Concentration Abs. of S-B 9 alkafeel.edu.iq [email protected]  Thank you 4 Listing 10 alkafeel.edu.iq [email protected]  Biochemistry//Liver Enzymes By Asst.L.Sara Sattar Jabbar lec.3 1 alkafeel.edu.iq [email protected]  The liver importance in intermediary metabolism and in the detoxification and elimination of toxic substances one of the largest organs in the human body it constitutes only 2-3% of the body mass, it accounts for 20-30% of the total oxygen consumption Liver Enzymes Aspartate Transferase (AST) Alanine Transaminase (ALT) Alkaline phosphatase (ALP) total protein (TP). Albumin Bilirubin 2 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  The uptake of nutrients delivered from the digestive tract via the portal vein The synthesis, storage, interconversion, and degradation of metabolites The regulated supply of energy-rich intermediates and building blocks for biosynthetic reactions The detoxification of harmful compounds by biotransformation The excretion of substances with the bile, as well as the synthesis and degradation of many blood plasma components 3 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  is an enzyme found in the liver that helps convert proteins into energy for the liver cells. When the liver is damaged, ALT is released into the bloodstream and levels increase is an enzyme found in the liver and bone and is important for breaking down proteins. Higher-than-usual levels of ALP may mean liver damage or disease, such as a blocked bile duct, or certain bone diseases, as this enzyme is also present in bones. is quantitatively the most important protein in plasma. Albumin is a major factor for maintaining oncotic intravascular pressure. It also plays an important role in transporting external or internal materials. Blood albumin is manufactured at a high rate in the liver. 4 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Bilirubin is an orange-yellow pigment that occurs normally when part of red blood cells break down. *A bilirubin test measures the amount of bilirubin in the blood. It's used to help find the cause of health conditions like jaundice, anemia, and liver disease. *If the bilirubin levels are higher than normal, it's a sign that either red blood cells are breaking down at an unusual rate or that the liver isn't breaking down waste properly and clearing the bilirubin from the blood. *High levels of bilirubin can cause a yellowing of the skin and eyes, a condition doctors call jaundice. Unconjugated (indirect) bilirubin. This type is created when hemoglobin from red blood cells is broken down, bound to a protein in the blood called albumin, and transported to the liver. Conjugated (direct) bilirubin. This type is created when bilirubin attaches to (conjugates with) glucuronic acid in the liver before being excreted. This type of bilirubin is what makes urine yellow. Total bilirubin. This refers to all of the bilirubin in the bloodstream. Total Serum Bilirubin test A bilirubin blood test measures the levels of bilirubin in your blood. Doctors use it to diagnose and monitor liver and bile duct diseases. These include cirrhosis, hepatitis, and gallstones. 5 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Clinical significant Increased Serum Bilirubin *Liver diseases, like hepatitis *Gilbert's syndrome, a genetic disease *Cirrhosis, which is scarring of the liver *Biliary stricture, where part of the bile duct is too narrow to allow fluid topass *Cancer of the gallbladder or pancreas *Gallstones *Drug toxicity *Jaundice 6 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  Proteins are important building blocks of all cells and tissues. Proteins are necessary for your body’s growth, development, and health. Blood contains albumin and globulin. Albumin proteins keep fluid from leaking out of your blood vessels. Globulin proteins play an important role in your immune system. Total protein content provides some information regarding a patient's general status; more clinically useful data are obtained from fractionating the total protein. The normal serum protein level is 6 to 8 g/dl. 7 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  :Liver diseases Risk Factors 1-Diabetes: metabolic disorder coinciding with hyperglycemia is due to a lack of synthesis or resistance to insulin or failure of its function , that leads to diabetic ketoacidosis and long-term complications such as nephropathy, retinopathy, neuropathy and cardiopathy. 2-body mass index (BMI) above 30kg/m2 it might increase the risk of developing T2DM 3-smoking 4- drinking alcohol 5- Obesity 6- Lipid Profiles: people with impaired lipid metabolism being one of the most important factors in its progression 8 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021  THANK U 4 LISTENING 9 alkafeel.edu.iq [email protected] Tuesday, August 24, 2021