Biochemistry Important Questions For MBBS 1st Year [Question Bank]

Here is a list of important Biochemistry questions for first-year MBBS students. Students can make use of this question bank for the preparation of the subject. For your convenience, the questions have been arranged in a chapter-wise format. 

As you complete each chapter in Biochemistry, refer to the following list of important questions.

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The questions have been divided into the following chapters:

  • Cell, Cellular Organelles and Membrane Transport
  • Carbohydrate Chemistry
  • Lipid Chemistry 
  • Protein Chemistry
  • Nucleic acid Chemistry 
  • Enzymes
  • Metabolism and homeostasis
  • Carbohydrate Metabolism
  • Lipid Metabolism
  • Protein and amino acid Metabolism
  • Nucleotide metabolism
  • Biological Oxidation 
  • Plasma proteins
  • Extracellular matrix
  • Vitamins
  • Minerals
  • Immunology
  • Nutrition
  • Water and electrolyte balance
  • Heme metabolism 
  • Molecular Biology
  • Molecular Biology Techniques
  • Biochemistry of Cancer
  • Organ function tests 
  • Free Radicals and Antioxidants 
  • Xenobiotics and Detoxification 
  • Clinical chemistry 

A star ★ indicates that the question is extremely important, so these should be the first ones to concentrate on.

Cell, Cellular Organelles and Membrane Transport

  • With a neat and labelled diagram, describe the structure and functions of the organelles present in a typical mammalian cell.
  • With a neat and labelled diagram, describe the structure of the plasma membrane/cell membrane (Fluid Mosaic Model). List down important functions. ★
  • Mitochondria – structure and important functions.
  • Endoplasmic reticulum – types and important functions.
  • Lysosome – important functions. Mention the marker enzymes. Give examples for lysosomal storage diseases. ★
  • Passive transport – Diffusion and Facilitated transport. ★
  • Active transport – Primary and Secondary. ★
  • Endocytosis and Exocytosis.

Carbohydrate Chemistry

  • Classification of carbohydrates with suitable examples. ★
  • Monosaccharides.
  • What are Mucopolysaccharides? Mention Describe their biomedical importance with suitable examples. ★
  • Compare and contrast the structural differences between starch and glycogen. ★
  • Epimerism and anomerism.
  • Mutarotation.
  • Why is sucrose a non-reducing sugar?
  • Composition of sucrose, maltose and lactose.

Lipid Chemistry 

  • Classification of lipids with suitable examples. ★
  • Essential fatty acids – definition, examples and important functions. ★
  • Prostaglandins.
  • Phospholipids – definition, types and functions. ★
  • Rancidity and lipid peroxidation.
  • Lung surfactant and Respiratory Distress Syndrome.
  • Cholesterol ‐ structure and biological importance. 

Protein Chemistry

  • Classification of amino acids based on nutritional requirement with suitable examples.
  • Classification of amino acids based on chemical structure with suitable examples.
  • Structural organisation of proteins (primary, secondary, tertiary and quaternary structure). ★
  • Bonds involved in stabilizing the structure of proteins. ★
  • Classification of proteins based on their biological function.
  • Biologically important peptides (biological importance of peptides).
  • Essential amino acids. ★
  • Isoelectric pH and isoelectric precipitation of proteins.
  • Denaturation of proteins and agents causing denaturation. ★
  • Glutathione. ★

Nucleic Acid Chemistry 

  • Watson and Crick model of DNA. ★
  • Structure and function of DNA.
  • Different types of RNA and their functions. ★
  • Difference between RNA and DNA. ★
  • Structure and function of mRNA.
  • Structure and function of tRNA. ★
  • Base pairing rule and Wobble hypothesis.

Enzymes

  • What are enzymes? Classify enzymes according to the IUBMB system with suitable examples. ★
  • Factors affecting enzymatic activity – enzyme concentration, pH, temperature and substrate concentration. ★
  • Km (Michaelis ‐Menton constant) with significance.
  • Enzyme inhibition – competitive, non competitive and uncompetitive. ★
  • Clinical importance of competitive enzyme inhibition.
  • Suicide inhibition.
  • Multienzyme complex.
  • Isoenzymes – definition, characteristics and clinical significance. ★
  • Diagnostic enzymes – examples and clinical significance. ★
  • Cardiac markers for myocardial infarction.
  • Hepato-biliary markers.
  • Therapeutic markers.

Metabolism and Homeostasis

  • Metabolic changes during starvation. ★
  • Metabolic changes during fed condition (absorptive state).
  • Hormonal regulation of blood glucose level. ★
  • Diabetes Mellitus – types, metabolic changes, complications. ★
  • Diagnosis of Diabetes Mellitus. ★
  • Glucose tolerance test. ★
  • Glycated haemoglobin. ★

Carbohydrate Metabolism

  • Digestion and absorption of carbohydrates.
  • Glucose transporters. ★
  • Lactose intolerance.
  • Glycolysis – significance, site, reactions, energetics, regulation and inhibitors. ★
  • Rapoport Luebering cycle with significance. ★
  • Lactic acidosis.
  • Citric acid cycle (TCA cycle) – significance, site, reactions, energetics, regulation, amphibolic role, anaplerotic reactions. ★
  • Gluconeogenesis. ★
  • Cori’s cycle.
  • Glycogenesis and Glycogenolysis. ★
  • Glycogen storage disorders (Glycogenosis). ★
  • HMP shunt pathway. ★
  • Uronic acid pathway.
  • Glucose‐6‐Phosphate dehydrogenase deficiency.
  • Galactosemia.
  • Essential Fructosuria.
  • Hereditary fructose intolerance.

Lipid Metabolism

  • Digestion and absorption of lipids. ★
  • Malabsorption syndrome.
  • Steatorrhea.
  • Beta oxidation of fatty acids. ★
  • Lipid storage diseases (Sphingolipidoses).
  • Ketogenesis, ketolysis and ketosis. ★
  • Synthesis of cholesterol. Add a note on its fate.
  • Synthesis and function of bile acids and bile salts. ★
  • Lipoproteins – Chylomicrons, VLDL, LDL, HDL. ★
  • Hypercholesterolemia and associated disorders. Add a note on hypocholesterolemic agents.
  • Fatty liver – definition and causes. ★
  • Lipotropic factors.

Protein and Amino Acid Metabolism

  • Digestion and absorption of proteins.
  • Amino acid pool.
  • Nitrogen balance.
  • Catabolism of amino acids.
  • Transamination.
  • Sources and fate of ammonia.
  • Urea cycle (Detoxification of ammonia). ★
  • Glycine – specialised products and their importance. ★
  • Phenylalanine and Tyrosine – metabolic pathway. ★
  • Metabolism of tryptophan. ★
  • Synthesis of catecholamines.
  • Polyamines ‐ examples and importance.
  • Phenylketonuria. ★
  • Alkaptonuria. ★
  • Albinism.
  • Homocystinuria.
  • Maple syrup urine disease.
  • Hartnup’s disease.
  • Carcinoid syndrome.

Nucleotide Metabolism

  • Sources of atoms of Purine ring. ★
  • Sources of atoms of Pyrimidine ring. ★
  • Salvage pathways of Purine and Pyrimidine synthesis.
  • Catabolism of Purine nucleotides. ★
  • Disorders of purine metabolism – Gout, Lesch Nyhan syndrome (etiology, clinical manifestations and biochemical basis). ★

Biological Oxidation 

  • Electron transport chain – components and inhibitors. ★
  • Oxidative phosphorylation – chemiosmotic hypothesis and inhibitors. ★
  • Uncouplers. ★
  • Brown adipose tissue.
  • Malate shuttle.
  • High energy compounds.

Plasma Proteins

  • Plasma proteins – types, functions and clinical significance. ★
  • Acute phase protein and clinical significance.
  • C reactive protein.
  • Multiple Myeloma. ★
  • Bence Jones Protein.

Extracellular Matrix

  • Collagen – composition, structure and function. ★
  • Abnormalities in collagen structure – Osteogenesis Imperfecta, Ehler‐Danlos syndrome. ★
  • Elastin.
  • Proteoglycans. ★

Vitamins

  • Water and fat soluble vitamins.
  • RDA, Sources, Biochemical functions, Deficiency manifestations, Hypervitaminosis of Fat soluble vitamins – A ★, D ★, E, K.
  • RDA, Sources, Biochemical functions, Deficiency manifestations, Hypervitaminosis of Water soluble vitamins – Vitamin C ★, Thiamine (Vitamin B1) ★, Riboflavin (Vitamin B2), Niacin (Vitamin B3), Pyridoxine (Vitamin B6), Biotin, Pantothenic acid (Vitamin B5), Folic acid (Vitamin B9), Cobalamin (Vitamin B12).
  • Antivitamins.
  • Why does Vitamin E have sparing action on Selenium?
  • Beri beri.
  • Pellagra.

Minerals

  • Major elements and trace elements.
  • Sources, RDA, Absorption, Transport, Biological functions, Biological reference range, Disorders – Calcium ★, Phosphorus, Iron ★.
  • Calcium homeostasis (regulation of plasma calcium level).
  • Functions and disorders associated with ‐ Copper ★, Zinc, Selenium ★, Fluoride, Iodine, Magnesium ★, Molybdenum.
  • Tetany.
  • Wilson’s disease.
  • Fluorosis.
  • Iron deficiency anemia.

Immunology 

  • Classification of immunoglobulins. ★
  • Structure of immunoglobulin. ★
  • Cellular and humoral immunity.
  • Role of T‐helper cells in immune responses.
  • Autoimmunity.
  • Types of vaccines and immunological basis of vaccine development. ★

Nutrition

  • Basal Metabolic Rate (BMR) – definition, normal value, factors affecting and significance. ★
  • Specific Dynamic Action (SDA) – definition, normal value, and significance. ★
  • Nitrogen balance.
  • Balanced diet – definition, composition.
  • Dietary fibers – definition, examples, significance. ★
  • Calculation of calorie requirement.
  • Protein Energy Malnutrition (PEM) – Kwashiorkor and Marasmus. ★
  • Complementary proteins.
  • Obesity.
  • Acid base balance.
  • Regulation of pH of blood by buffers, respiratory and renal mechanisms. ★
  • Anion gap. ★
  • Acidosis and alkalosis (metabolic and respiratory) – causes, compensatory mechanismsand lab findings. ★

Water and Electrolyte Balance

  • Regulation of water and electrolyte balance. ★
  • Renin angiotensin aldosterone mechanism. ★
  • Disorders of electrolyte imbalance – causes and clinical features of Hyperkalemia ★, Hypokalemia, Hypernatremia, Hyponatremia.

Heme Metabolism 

  • Heme synthesis. ★
  • Porphyrias. ★
  • Degradation of Heme (formation of Bilirubin). ★
  • Jaundice – definition, classification, causes, lab diagnosis. ★
  • Congenital hyperbilirubinemias – Crigler-Najjar syndrome, Dubin Johnson syndrome, Gilbert’s disease.
  • Hemoglobin – types, structure and function.
  • Abnormal hemoglobins.
  • Hemoglobinopathies – thalassemias and sickle cell anemia.

Molecular Biology

  • DNA replication ‐ prokaryotic and eukaryotic replication, requirements, process, inhibitors.
  • DNA polymerases.
  • Okazaki fragments.
  • Transcription –  Transcriptional units, promoter regions, RNA polymerases in prokaryotes and eukaryotes, process, inhibitors. ★
  • Differences between prokaryotic and eukaryotic transcription.
  • Post transcriptional modifications. ★
  • Translation in Eukaryotes – process, inhibitors. ★
  • Post translational modifications. ★
  • Genetic code and its characteristics. ★
  • Regulation of gene expression in prokaryotes (Lac Operon concept). ★
  • Regulation of gene expression in eukaryotes.

Molecular Biology Techniques

  • Recombinant DNA technology. ★
  • DNA cloning ‐ process and application.
  • PCR – requirement, steps and application. ★
  • Blotting techniques – southern blotting ★, northern blotting, western blotting.
  • Vectors. ★
  • Gene therapy. ★
  • DNA Probes. ★
  • RFPL.

Biochemistry of Cancer

  • DNA repair mechanisms. ★
  • Xeroderma Pigmentosum.
  • Mutations – causes, types, consequences and examples. ★
  • Mutagens and carcinogens.
  • Tumour markers and their importance in diagnosis and prognosis of cancer. ★
  • Oncogenes. ★
  • Proto Oncogenes and their activation. ★
  • Tumour suppressor genes.
  • Oncogenic viruses.
  • Reverse transcriptase. ★
  • Growth factors.

Organ Function Tests 

  • Liver Function Tests. ★
  • Renal Function tests. ★
  • Mechanism of action of Group I ★ and Group II hormones.
  • Thyroid function tests. ★
  • Adrenal function tests.

Free Radicals and Antioxidants 

  • Free radicals. ★
  • Reactive oxygen species (ROS). ★
  • Damaging effects of ROS on biomolecules, lipid peroxidation. ★
  • Anti‐oxidant defence system of our body – enzymes, vitamins, metabolites as antioxidants.

Xenobiotics and Detoxification 

  • Biotransformation.
  • Phase I reactions – Oxidation, Reduction, Hydroxylation. ★
  • Cytochrome P450.
  • Phase II reactions – Conjugation. ★

Clinical Chemistry 

  • Automation ‐ advantages. ★
  • Quality control. ★
  • Biological reference intervals. ★
  • Critical alerts.

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Good luck Medicoholics! Until next time.

4 thoughts on “Biochemistry Important Questions For MBBS 1st Year [Question Bank]”

  1. This is really so helpful especially for MBChB students. It’s got much information to be able to help a student pass the exams.

    Reply

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