Biochemistry Lecture Notes PDF

LECTURE 1 1. What is the basic structural representation of amino acids? Amino group, carboxylic group, side chain 2. How many amino acids exist in the human body? 20 3. How many amino acids are present in a tripeptide?3 amino acid 4. How many peptide bonds are present in a dipeptide? 1 5. Give an e...

LECTURE 1 1. What is the basic structural representation of amino acids? Amino group, carboxylic group, side chain 2. How many amino acids exist in the human body? 20 3. How many amino acids are present in a tripeptide?3 amino acid 4. How many peptide bonds are present in a dipeptide? 1 5. Give an example of a sulfur-containing amino acid. Cysteine and Methionine 6. Give an example of an aromatic amino acid. Phenylalanine ,Tyrosine, Tryptophan 7. Which amino acid is named as Imino acid?proline LECTURE 2 1. Give an example of a purely Ketogenic amino acid.Leucine 2. Give examples of essential amino acids.MeTTVILPhLy (Methionine,Threonine,Tryptophan ,Valine, Isoleucine, Leucine, Phenylalanine and Lysine ) 3. The amino acids that are synthesized by the human body and hence not required through diet are termed as....Non essential 4. The amino acids that are not synthesized by the human body and hence required through diet are termed as … essential 5. Give examples of derived amino acids.Hydroxy proline and hydroxy lysine § Citrulline and Homocysteine § Gamma Amino Butyric Acid (GABA) 6. Give examples of acidic amino acids.Aspartic acid and Glutamic acid 7. Give examples of basic amino acids.Lysine, Arginine and Histidine LECTURE 3 1. Give examples of proteins that contain! A. One polypeptide Albumin B. Two polypeptides Insulin C. Three polypeptides collagen D. Four polypeptides Hemoglobin 2. Discuss the different proteins classified based on their function. 3. List the different types of conjugated proteins. Proteins that contain a protein part and non protein part (prosthetic group) Examples: Glycoproteins, Lipoproteins, Nucleotides, chromoproteins, phosphoproteins, Metalloproteins 4. Give an example of a protein that contains all the essential amino acids (nutritionally rich protein). Casein of milk LECTURE 4 1. Plasma proteins synthesized in the liver whose concentrations increase or decrease by 25% or more during inflammation are termed as.....Acute phase proteins 2. Give examples of acute-phase proteins.C-reactive protein, heptoglobin, fibrinogen and ą-1 antitrypsin etc 3. What are the major plasma proteins present in blood?albumin, globulins and fibrinogen 4. List the functions of Albumin colloidal osmotic, Transport, Nutrition, buffering Globulin immune system, transport Fibrinogen involved in blood coagulation and soluble fibrinogen cane form as in insoluble fibrin clot 5. What are the two major differences between serum and plasm? Plasma = Blood – Cell components.Serum = Plasma – Fibrinogen (Blood clotting factor) Serum A clear, pale-yellow fluid and Separated from clotted blood (by centrifugation) PlasmaA clear or slightly cloudy, pale-yellow fluid and Separated from unclotted blood in an anticoagulant tube (by centrifugation) 6. Which plasma protein is the fastest-moving protein during electrophoresis? Albumin LECTURE 5 1. The glycoproteins that recognize, bind and destroy specific antigens are termed as immunoglobulins 2. List major types of immunoglobulins.lgA , lgD, lgE, lgG,lgM 3. How many polypeptide chains are present in the basic structure of immunoglobulins?4 chain (2 light and 2 heavy) 4. Which bond links the heavy and light chains in an immunoglobulin?disulfide bonds 5. Which immunoglobulin exists as a dimer? IgA 6. Which immunoglobulin exists as a pentamer? IgM 7.Discuss the major functions of different immunoglobulins. Lecture 6 1.Which one is the tetrameric oxygen transport protein found in red blood cells(erythrocytes)?Hemoglobin 2. Which one is the monomeric oxygen transport protein found in muscles?myoglobin 3. What are the two major functions of haemoglobin? Transport of oxygen from the lungs to the tissues. Transport of carbon dioxide from tissues to lungs for excretion. 4. What are the two major functions of myoglobin? Myoglobin serves as an intracellular storage site for oxygen. Myoglobin supplies oxygen to the cells in the muscles. 5.Which one is the protein part of haemoglobin?Globin 6. Which one is the non-protein part of haemoglobin?Heme 7. How many polypeptides are present in haemoglobin?4 polypeptide 8. Which are polypeptides present in adult haemoglobin?adult hemoglobin (HbA1) is made up of two α-chains and two β-chains (α2β2) 9. Which are the groups attached to the four pyrole rings of Protoporphyrin IX? Four methyl groups, Two propionyl groups Two vinyl groups 10. What are the major clinical conditions associated with Low Hb levels? LECTURE 7 1. Give examples for monosaccharides. 2. Give examples for disaccharides. Maltose Lactose Sucrose 3. Give examples for polysaccharides. 4. Give examples for pentoses and hexoses. 5. Carbohydrates having 2-10 sugar units are called as oligosaccharides 6. Carbohydrates having more than 10 sugar units are called as Polysaccharides 7. What are the products of hydrolysis of Maltose, Lactose and Sucrose? 8. Polysaccharides having only one type of monosaccharide units are called Homopolysaccharides LECTURE 9 1. Define fatty acids.aliphatic carboxylic acids with a hydrocarbon chain. 2. Classify fatty acids based on the nature of the hydrocarbon chain. 3. Classify fatty acids based on nutritional statu 4. Give examples for essential fatty acids. Linoleic Acid (18:2) Linolenic Acid (18:3) Arachidonic Acid (20:4) 5. Give examples for non-essential fatty acids. All other fatty acids e.g. Palmitic Acid (16:0) LECTURE 12 1. What is the between free cholesterol and cholesterol ester. 2. What are the classes of Lipoproteins depending on the density? the lipoproteins in plasma are classified into five major types 1. Chylomicrons 2. VLDL 3. IDL 4. LDL 5. HDL 3. What are the functions of HDL and LDL? 4. What are the types of plasma cholesterol? 5. What is the clinical importance of blood cholesterol? Hypocholesterolemia and Hypercholesterolemia 6. What is the clinical importance of HDLC and LDLC? High levels of LDLC (> 130 mg/dL) and low levels of HDLC (< 40 mg/dL) are known risk factors (along with obesity, hypertension, diabetes mellitus, smoking and stress) in the development of Coronary Heart Disease. 7. The thickening or hardening of the arteries by a build-up of plaque in the inner lining of the artery is termed as Atherosclerosis 8. A condition caused by excessive fat build-up in the liver is termed as Fatty liver disease LECTURE 13 1. The complex organic molecules consisting of many nucleotides linked in a long chain are termed as Nucleic acids 2. The two-ringed nitrogenous bases are termed as Adenine Guanine 3. The single-ringed nitrogenous bases are termed as Cytosine Thymine Uracil 4. What is the composition of nucleosides? Two a. Nitrogenous base, (a purine or a pyrimidine) b. Pentose sugar, either ribose or deoxyribose; 5. What is the composition of nucleotides? Three a. Nitrogenous base, (a purine or a pyrimidine) b. Pentose sugar, either ribose or deoxyribose; c. Phosphate groups esterified to the sugar. 6. What is the composition of ATP? adenosine triphosphate includes adenine (a nitrogenous base), ribose (a five-carbon sugar), and three phosphate groups. 7. Which nitrogenous bases are present in DNA? Adenine, guanine,cytosine,thymine 8. Which nitrogenous bases are present in RNA? Adenine, guanine,cytosine,uracil 9. How many strands are present in RNA and DNA? DNA = double stranded RNA = single stranded LECTURE 15 1. The balance between nitrogen intake through the diet and nitrogen excretion from the body is termed asNitrogen balance 2. What is the action of endopeptidase and exopeptidase? Endopeptidases break internal peptide bonds in the protein. Exopeptidases cleave amino acids on the terminal end of the protein molecule. 3. Which one is the end product of the urea cycle?urine 4. What is meant by decarboxylation, transamination and deamination? Decarboxylation : The amino acids undergo decarboxylation to form the corresponding amine. Transamination:The amino group of amino acid can be transferred to keto acid to form the corresponding new keto acid and amino acid. Deamination: The amino group is removed from the amino acid to form the corresponding keto acid and ammonia. 5. The process by which DNA is converted to mRNA is termed as transcription 6. The process by which mRNA is converted to protein is termed as Translation 7. Biologically important compounds synthesized from amino acids. Glutathione,melatonin , serotonin,creatine,creatinine, nitric oxide LECTURE 16 1. Define glycolysis, gluconeogenesis, glycogenesis and glycogenolysis. Glycolysis is the process in which glucose undergoes breakdown to produce pyruvate or lactate under aerobic or anaerobic conditions respectively which results in the release of energy. Gluconeogenesis is the process in which glucose is synthesized from noncarbohydrate sources. Glycogenolysis is the process in which glycogen undergoes breakdown to produce glucose. Glycogen phosphorylase is the enzyme that regulates the glycogenolysis in the liver and muscles. Glycogenesis is the process in which glycogen is synthesized from glucose. 2. Which carbohydrate-splitting enzyme is present in saliva?amylase 3. What is the net energy yield during aerobic and anaerobic glycolysis? Aerobic Conditions: 7 ATPs Anaerobic Conditions: 2 ATPs 4. What is the net energy yield from 1 Acetyl CoA during TCA cycle?3 NADH , 1 FADH2 ,1 ATP 5. Explain the role of hormones in the regulation of blood glucose. LECTURE 17 1. What is meant by beta-oxidation?β-oxidation is the process by which fatty acids are broken down to acetyl-CoA. 2. What are the end-products of beta-oxidation?Acetyl CoA, FADH2 ,NADH 3. What are the precursors for the fatty acid synthesis?Acetyl-CoA and NADPH 4. Give examples of ketone bodies. Acetone, Acetoacetate and Beta-hydroxybutyrate 5. What are the biologically important compounds synthesized from cholesterol?Bile acids/salts, Steroid hormones and Vitamin D LECTURE 18 1. What are the precursors for the de novo synthesis of purine nucleotides? Phosphoribosyl pyrophosphate (PRPP) and Glutamine 2. What is the end-product of purine nucleotide degradation?uric acid 3. What are the precursors for the synthesis of pyrimidine nucleotides?Glutamine, ATP and Bicarbonate 4. What are the major disorders associated with nucleic acid metabolism? LECTURE 20 1. What are the precursors for the biosynthesis of heme?glycine, succinylcholine 2. Which are the two enzymes involved in the degradation of heme?hemoxygenase,biliverdin reductase 3. Which one is the end-product of heme catabolism?bilirubin 4. What are the different types of bilirubin?unconjugated, conjugated, total 5. What is meant by hyperbilirubinemia? hyperbilirubin - above normal bilirubin increase in serum total bilirubin level >1.2 mg/dL 6. What are the major clinical conditions associated with hyperbilirubinemia?jaundice, liver disease, hemolytic anaemia 7. What is the diagnostic criteria for jaundice? jaundice (above 2.5 bilirubin) The level of bilirubin >2.5 mg/dL indicates Increased bilirubin LECTURE 21 1. Which are the biological catalysts synthesized by living cells capable of acting independently of the cells without itself undergoing any chemical change?Enzymes 2. Which one is the region of an enzyme where substrate molecules bind and undergo a chemical reaction? active site 3. Which are the six classes of enzymes?Oxidoreductases, Transferases, Hydrolases, Lyases, Isomerases, Ligases 4. What are the functions of the six classes of enzymes? Oxidoreductases : Catalyze oxidationreduction (redox) reactions. (Example:Dehydrogenase) Transferases : Catalyze the transfer of functional groups from one molecule to another.(Example:Transaminase, transmethylase, kinase) Hydrolases : Catalyze hydrolysis reactions.(Example:Glycosidase, protease, lipase) Lyases : Catalyze the addition of a group to a double bond or the removal of a group to form a double bond.(Example:Fumerase) Isomerases : Catalyze the conversion of one isomer into another(Example:Mutase) Ligases : Catalyze the joining of two molecules using ATP for energy.(Example:DNA ligase) 5. What is meant by isoenzymes? Isozymes are physically distinct forms of the same enzymes that catalyze the same biochemical reaction. Isozymes are formed by different genes and have different molecular shapes. 6. Give examples of isoenzymes./ Example 1:Lactate Dehydrogenase has 5 isoenzymes Example 2: Creatine kinase (CK) has three forms:CK-1 (CK-BB), CK-2 (CK-MB),CK-3 (CK-MM) 7. What is the clinical significance of CK-MB and CK-MM? LECTURE 22 1. What are the 4 major mechanisms of action for enzymes? 1. Lowering activation energy 2. Michaelis-Menten theory 3. Fischer’s lock and key hypothesis 4. Koshland’s induced fit theory 2. Which mechanism explains that the enzyme changes its shape when the substrate binds?Koshland’s induced fit 3. Differentiate between competitive, non-competitive and uncompetitive inhibition. competitive :It binds to the active site. non-competitive:It binds to the allosteric site. uncompetitive : It binds to the E-S complex LECTURE 23 1. What are the factors influencing the enzymatic reaction? Temperature, pH, substrate of condensation , enzyme of concentration, presence of inhibitors, presence of activators,presence of repressor, Availability of co-enzymes, covalent modification 2. What is the reason for decreasing the rate of enzymatic reaction after the optimum pH? Denaturation of the enzyme 3. Define Vmax :maximum velocity obtained in the presence of excess substrate. 4. Define Km: substrate concentration at half maximum velocity (½ Vmax) 5. What is the effect of a competitive inhibitor on Vmax and Km? vmax doesn’t change, km increases 6. What is the effect of a non-competitive inhibitor on Vmax and Km?vmax decreases, km doesn’t change LECTURE 24 1. Which are the fat-soluble vitamins? 2. Which are the water-soluble vitamins? 3. What are the deficiency disorders of vitamins A and D? 4. What are the deficiency disorders of Thiamine and Niacin? 5. Which one is the deficiency disorder of vitamin C? 6. What is meant by hypervitaminosis?occurs when the storage levels of vitamins are abnormally high. Hypervitaminosis can lead to toxic symptoms and diverse health effects. LECTURE 25 1. What are the differences between major minerals and trace minerals? 2. What biochemical terms are used for low and high levels of Ca, Mg, P, Na, K and CI? 3. Deficiency of which mineral is indicated by anemia? Iron 4. Which disorder results from iodine deficiency?Goitre Good luck H.M