L4 QS BANK, BMS201 PDF Medical School Questions
Document Details
Uploaded by MedPrime
New Mansoura University
Tags
Summary
This document contains multiple choice questions (MCQs) related to bilirubin, jaundice, and related physiological concepts. It covers questions regarding the lifecycle of red blood cells, the role of various enzymes, and the causes and characteristics of different types of jaundice.
Full Transcript
Part One: Simple MCQs 1. What is the average lifespan of red blood cells (RBCs)? a) 30 days b) 60 days c) 120 days d) 180 days 2. Where does the majority of heme catabolism take place? a) Kidneys b) Bone marrow c) Reticuloendothelial system (RES) d) Lungs 3. Which enzyme catalyzes the conversio...
Part One: Simple MCQs 1. What is the average lifespan of red blood cells (RBCs)? a) 30 days b) 60 days c) 120 days d) 180 days 2. Where does the majority of heme catabolism take place? a) Kidneys b) Bone marrow c) Reticuloendothelial system (RES) d) Lungs 3. Which enzyme catalyzes the conversion of heme to biliverdin? a) Biliverdin reductase b) Heme oxygenase c) Bilirubin UDP-glucuronyl transferase d) Ferrochelatase 4. What is the color of biliverdin? a) Red b) Yellow c) Green d) Blue 5. Which type of bilirubin is water-soluble? a) Unconjugated bilirubin b) Conjugated bilirubin c) Both are water-soluble d) Neither is water-soluble 6. Where does the conjugation of bilirubin occur? a) Spleen b) Liver c) Intestines d) Blood 7. Which enzyme is responsible for the conjugation of bilirubin? a) Heme oxygenase b) Biliverdin reductase c) Bilirubin UDP-glucuronyl transferase d) UDP-glucose dehydrogenase 8. What is the primary cause of hemolytic jaundice? a) Liver disease b) Bile duct obstruction c) Increased red blood cell breakdown d) Decreased bilirubin excretion 9. Which type of jaundice is characterized by an increase in conjugated bilirubin? a) Hemolytic jaundice b) Obstructive jaundice c) Neonatal jaundice d) Gilbert's syndrome 10. What is the normal level of bilirubin in plasma? a) Up to 0.5 mg/dl b) Up to 1 mg/dl c) Up to 2 mg/dl d) Up to 3 mg/dl Answer Guide Part One 1. c 2. c 3. b 4. c 5. b 6. b 7. c 8. c 9. b 10. B 11. Part Two: Complex MCQs 1. Which of the following best describes the role of the reticuloendothelial system (RES) in red blood cell destruction and heme catabolism? a) It synthesizes new red blood cells to replace old ones b) It transports bilirubin from the blood to the liver c) It phagocytoses old red blood cells and breaks down hemoglobin, initiating heme catabolism d) It converts conjugated bilirubin to unconjugated bilirubin 2. Which of the following sequences accurately represents the key steps in the conversion of heme to bilirubin? a) Heme -> Bilirubin -> Biliverdin -> Iron b) Heme -> Biliverdin -> Bilirubin -> Iron c) Heme -> Iron -> Biliverdin -> Bilirubin d) Heme -> Iron -> Bilirubin -> Biliverdin 3. Which of the following statements correctly differentiates unconjugated and conjugated bilirubin? a) Unconjugated bilirubin is water-soluble, while conjugated bilirubin is water-insoluble b) Unconjugated bilirubin is transported freely in the blood, while conjugated bilirubin binds to albumin c) Unconjugated bilirubin is elevated in obstructive jaundice, while conjugated bilirubin is elevated in hemolytic jaundice d) Unconjugated bilirubin is produced in the RES, while conjugated bilirubin is produced in the liver 4. What is the primary biochemical basis of jaundice? a) Increased production of red blood cells b) Decreased excretion of bile salts c) Accumulation of bilirubin in the blood and tissues d) Deficiency of iron 5. Which of the following statements accurately describes neonatal jaundice and its treatment? a) It is a rare condition caused by excessive bile production in newborns b) It is caused by a deficiency of UDP-glucuronyl transferase and is treated with blood transfusions c) It is a common condition caused by immature liver function and is treated with phototherapy or phenobarbital d) It is a serious condition requiring immediate liver transplantation 6. Match the type of jaundice with its cause and the type of bilirubin that is elevated: Type of Cause Elevated Bilirubin Jaundice Hemolytic Increased red blood cell Unconjugated breakdown Obstructive Bile flow obstruction Conjugated Hepatocellular Liver disease Both unconjugated and conjugated 7. What is the role of UDP-glucuronyl transferase in bilirubin metabolism, and how does its deficiency lead to jaundice? a) It converts biliverdin to bilirubin, and its deficiency leads to the accumulation of biliverdin b) It conjugates bilirubin with glucuronic acid, making it water-soluble, and its deficiency leads to the accumulation of unconjugated bilirubin c) It transports conjugated bilirubin into the bile, and its deficiency leads to the accumulation of conjugated bilirubin in the liver d) It breaks down bilirubin in the intestines, and its deficiency leads to increased reabsorption of bilirubin 8. Which of the following best describes the enterohepatic circulation of bilirubin? a) It is the process of bilirubin excretion in the urine b) It is the conversion of bilirubin to urobilinogen in the intestines c) It is the reabsorption of some conjugated bilirubin from the intestines back into the blood d) It is the transport of bilirubin from the liver to the gallbladder 9. Which of the following is characteristic of Gilbert's syndrome? a) Severe jaundice with neurological symptoms b) Mild, asymptomatic jaundice or mild jaundice triggered by stress or fasting c) Dark urine due to increased excretion of conjugated bilirubin d) Complete absence of UDP-glucuronyl transferase activity 10. What is the key difference between Crigler-Najjar syndrome and Gilbert's syndrome? a) Crigler-Najjar syndrome is caused by a mild deficiency of UDP-glucuronyl transferase, while Gilbert's syndrome is caused by a severe deficiency b) Crigler-Najjar syndrome presents with mild jaundice, while Gilbert's syndrome presents with severe jaundice c) Crigler-Najjar syndrome is a benign condition, while Gilbert's syndrome can lead to kernicterus d) Crigler-Najjar syndrome is a severe condition that can lead to kernicterus, while Gilbert's syndrome is a mild condition with usually no significant clinical consequences 11. Which of the following statements accurately describes the defect in Dubin-Johnson syndrome? a) Deficiency of UDP-glucuronyl transferase b) Defective transporter protein for hepatic secretion of conjugated bilirubin c) Increased red blood cell breakdown d) Bile duct obstruction 12. A patient presents with jaundice and elevated levels of unconjugated bilirubin. Which of the following could be a possible cause? a) Hemolytic anemia b) Gallstones c) Hepatitis d) Pancreatic cancer 13. How does phototherapy help in treating neonatal jaundice? a) It stimulates the production of UDP-glucuronyl transferase b) It converts unconjugated bilirubin to a water-soluble form that can be excreted without conjugation c) It increases the excretion of bilirubin in the urine d) It breaks down bilirubin in the blood 14. Which of the following is a potential consequence of untreated jaundice, especially in newborns? a) Kernicterus (bilirubin deposition in the brain) b) Liver failure c) Kidney failure d) Heart disease 15. A patient with a history of gallstones presents with jaundice and elevated levels of conjugated bilirubin. What is the most likely cause of their jaundice? a) Hemolytic anemia b) Hepatitis c) Obstructive jaundice due to gallstones blocking the bile duct d) Crigler-Najjar syndrome Part Two: Complex MCQs Answer Guide 1. c 2. b 3. d 4. c 5. c 6. Type of Cause Elevated Bilirubin Jaundice Hemolytic Increased red blood cell Unconjugated breakdown Obstructive Bile flow obstruction Conjugated Hepatocellular Liver disease Both unconjugated and conjugated 7. b 8. c 9. b 10. d 11. b 12. a 13. b 14. a 15. c