BIOCHEMISTRY, BIOMEDICINE & PHARMACEUTICS

Multiple Choice Question on Heme synthesis & Related Inherited Disease (Porphyria) In this page, we will review the multiple-choice practice questions on heme synthesis and related inherited disorders including hepatic and erythropoietic porphyria. The biological importance of heme, heme biosynthesis, regulation of heme synthesis, diagnosis, and treatment of porphyria are discussed elsewhere and a link for the page is provided below.   Heme is an essential molecule for various biological functions. It plays a crucial role in oxygen transport, energy metabolism, and the functioning of various enzymes. Heme synthesis is regulated to maintain the balance of heme levels in the body. The regulation is primarily achieved through feedback inhibition, where the final product, heme, inhibits the activity of the enzyme ALA synthase to prevent excess heme production. Please review the topics by clicking the link provided below: Page Links  Heme Biosynthesis and Regulation  Disor...

Multiple Choice Question on Cytokines, Interferon & Interleukins 1) Cytokines regulate the intensity and duration of the immune response by activating or downregulating both innate and adaptive immune responses.  The mode of action of the cytokine is the following, Except ? a) Autocrine b) Paracrine c) Endocrine d) Cell-autonomous 2) The characteristic properties of cytokines are : a) pleiotropy and redundancy b) synergy and antagonism c) cascade induction and amplification d) All of the above 3) Which of the following class of cytokine receptors utilize G-protein coupled receptors for its downstream function? a) Chemokines receptor b) Hematopoietic receptor c) Interferon receptor d) None of the above 4) Tumor necrosis factor (TNF) is an endogenous pyrogen that induces fever.  Which of the following statement is true regarding TNF, Except? a) TNF induces IL-1 production for induction of fever b) TNF induces the synthesis of prostaglan...

                         Multiple Choice Questions on Bile Acid Metabolism 1) Most of the plasma proteins are synthesized in the liver.  Which of the following plasma protein is not synthesized in the liver? a) Albumin b) Transferrin c) Ceruloplasmin d) von Willebrand factor 2) Which of the following is not the metabolic function of the liver? a) Synthesis and assembly of chylomicrons b) Synthesis and secretion of bile acids c) Synthesis and breakdown of glycogen d) Gluconeogenesis 3) Bile acids are conjugated to amino acids or taurine to form bile salts.  Which of the following amino acid is utilized for conjugation reaction? a) Alanine b) Glycine c)Valine d)Leucine 4) Cholic acid and Chenodeoxycholic acid are the primary bile acid synthesized in the liver.  The bile acid is converted into secondary bile acids (eg. deoxycholic acid) by ............................................................. a) E...

Multiple Choice Questions  on Host Defense Mechanism (Immunology) 1) Based on the principles of the ............................................. theory, each individual lymphocyte possesses a distinct membrane receptor tailored to a specific antigen. When the antigen binds to its corresponding receptor, it triggers an immune response targeted specifically against that particular antigen. a) Clonal selection theory b) Instructional theory c) Selective theory d) Germ theory 2) Immunity is the defense mechanism of the body that protects against foreign pathogens. The immunity can be classified into innate immunity and acquired immunity.  Which of the following statements is FALSE concerning innate immunity? a) It exhibits a broad specificity against foreign antigens. b) It is present before exposure to antigens. c) It has memory cells. d) None of the above. 3) Which type of immunity develops after exposure to specific antigens? a) Acquired immunity  ...

                                        MCQs on Plasma Proteins 1) Plasma proteins are composed of mostly glycoproteins, lipoproteins, and immunoglobulins that function in the immune system; binding and transporting nutrients, toxic substances, metals, etc. The normal reference range for total plasma proteins is ............................ a) 2.5-4.5 gm / dl b) 4.5-6.0 gm / dl c) 6.0-8.3 gm / dl 4) >8.3gm / dl 2) Albumin and globulin (A&G) are the two important group of plasma proteins, the reference range for the A: G ratio is 0.8-2.0. Based on the electrophoretic mobility, the globulin fraction may be further classified into alpha-1 globulin, alpha-2 globulin, beta-globulin, and gamma-globulin. Which of the following protein is present in the gamma-globulin fraction ? a) Ceruloplasmin b) Haptoglobin c) Immunoglobulin d) Transthyretin 3) C-reactive protein, a plasma prot...

Multiple Choice Questions on Purine & Pyrimidine Metabolism Purine metabolism is a crucial biochemical process that involves the biosynthesis, degradation, and recycling of purine nucleotides, which are essential building blocks of DNA and RNA. The de novo biosynthesis of purines requires several enzymes, including glutamine: phosphoribosyl pyrophosphate (PRPP) amidotransferase, which is a committed step and a target for regulation. Other important enzymes involved in purine biosynthesis include adenylosuccinate synthetase and adenylosuccinate lyase. The degradation of purine nucleotides generates uric acid, which is excreted by the kidneys. Dysregulation of purine metabolism can lead to several diseases, including gout and Lesch-Nyhan syndrome. Understanding the complex regulation of purine metabolism is crucial for the development of novel therapeutic strategies. 1. The function of nucleotide includes : a) Second Messenger b) Energy currency and high energy equivalents c...

                      Multiple Choice Question on Lipid Metabolism ( Cholesterol, Triglycerides, and                               Other Lipids ) 1) The cholesterol serves as the precursor for the following biosynthetic pathways,  EXCEPT a) Bile acid synthesis b) Steroid hormone synthesis c) Aldosterone synthesis d) Thyroid hormone synthesis 2) Which of the following lipids act as lungs surfactants? a) Phosphatidylcholine b) Phosphatidylethanolamine c) Ceramide d) Phosphatidylinositol 3) Identify the simple lipid from the following? a) Lecithin b) Fatty acid c) Triacylglycerol d) Steroids 4) All of the following are complex lipids, Except? a) Phosphatidic acid b) Cerebroside c) Cardiolipin d) Cholesterol 5) Which of the following is an essential fatty acid? a) Linolenic acid b) Arachidonic acid c) Oleic acid d) Palmitic...

                                        MCQs on Diabetes mellitus 1) Diabetes mellitus is a disorder characterized by hyperglycemia.  Which of the following is not the common characteristic features of type 2 diabetes mellitus ? a) Impaired insulin secretion b) Increased Insulin resistance  c) Diabetic ketoacidosis d) Excessive hepatic glucose production 2) Which of the following are the characteristic features of type 1 diabetes mellitus? a) Type 1 diabetes is caused by an absolute deficiency of insulin. b) Type 1 diabetes is associated with the autoimmune destruction of beta cells.  c) Patients with  uncontrolled type 1 diabetes present with diabetic ketoacidosis d) All of the above   3) Which of the following serum measurements are not used for the diagnosis of diabetes mellitus? a) Fasting blood glucose d) Postprandial blood glucose  c) Insulin ...