Endocrinology Quiz: Diabetes and Hormones

Questions and Answers

• Question 1: A patient with type 1 diabetes skips dinner after taking insulin. Three hours later, they feel shaky, sweaty, and confused. What caused this?

  • Low blood glucose levels.

• Question 2: A patient in question 19.1 falls asleep before paramedics arrive. What treatment would help reverse the effect of this?

  • Epinephrine.

• Question 3: What effect might drinking strong espresso have on the liver?

  • A prolonged response to glucagon.

• Question 4: A mutation in pancreatic glucokinase can lead to MODY. Which process is affected?

  • A reduced ability to raise ATP levels.

• Question 5: Which organ has the highest demand for glucose for fuel?

  • The brain.

• Question 6: Why doesn't glucagon affect muscle metabolism?

  • Muscle cells lack the glucagon receptor.

• Question 7: A patient experiences tremors, sweating, and a rapid heartbeat. What hormone is likely released?

  • Epinephrine.

• Question 8: Which meal will have the lowest circulating glucagon shortly after eating?

  • High-carbohydrate meal.

• Question 9: A 45-year-old patient is in a coma due to severe hyperglycemia. How can you determine if it's type 1 or type 2 diabetes?

  • Measure the C-peptide level.

• Question 10: High blood glucose levels in a patient's urine lead to cerebral dysfunction. What's the cause?

  • Dehydration.

• Question 1: Which transporter is most responsible for transporting fructose from the blood into cells?

  • GLUT 5.

• Question 2: A patient with alcoholism has pancreatitis and discomfort after a high-carbohydrate meal. What is the likely digestive issue?

  • Reduced ability to digest starch.

• Question 3: A man with type 1 diabetes skips insulin injections. Which tissue will be most affected?

  • Red blood cells.

• Question 4: What are the main carbohydrate products formed after digesting a cake (flour, milk, sucrose)?

  • Glucose, fructose, and galactose.

• Question 5: A patient with a genetic defect in intestinal epithelial cells cannot digest disaccharides. What would be elevated?

  • Maltose, sucrose, and lactose in the stool.

• Question 6: Which carbohydrate contains glucosyl units linked through alpha-1,6 glycosidic bonds?

  • Amylopectin.

• Question 7: A patient increases fiber intake but experiences abdominal cramping, bloating, and increased flatulence. What's the cause?

  • Bacteria in the colon convert fiber to H2, CO2, and methane.

• Question 8: A newly diagnosed patient with diabetes avoids table sugar but consumes fruits, fruit drinks, milk, honey, and vegetables, leading to poor diabetic control. What form of carbohydrate is primarily in their diet?

  • Glucose.

• Question 9: A 10-year-old develops severe diarrhea and now has digestive issues after drinking milk. What's the best advice?

  • Her ability to drink milk should return in a few days.

• Question 10: A runner wants a high glycemic index food for "carb loading". What should they choose?

  • Malted milk balls.

• Question 1: What is the body's universal fuel used by virtually all tissues?

  • Glucose.

• Question 2: What is a major role of glycolysis?

  • To generate energy.

• Question 3: What is the net yield of ATP and NADH from one glucose 1-P to two pyruvate molecules?

  • 2 ATP, 2 NADH.

• Question 4: What statement correctly describes an aspect of glycolysis?

  • Pyruvate kinase is the rate-limiting enzyme.

• Question 5: What is found in both the fructose metabolic pathway and the glycolytic pathway?

  • Glyceraldehyde 3-P.

• Question 6: A 4-week-old baby has frequent vomiting, tenderness, enlarged liver, and hints of cataracts. A urine dipstick test shows a positive result for a reducing sugar. What is the likely compound?

  • Glucose.

• Question 7: What intracellular metabolite allows for determination of an enzyme deficiency in the child from question #6?

  • Fructose 6-P.

• Question 8: What is one action of metformin in treating type 2 diabetes and why does it not cause lactic acidosis in practice?

  • Decreases hepatic gluconeogenesis. The Cori cycle deals with the lactate buildup in the liver.

• Question 9: What reaction commits glucose to the glycolytic pathway?

  • Glucose to glucose 6-P.

• Question 10: How do red blood cells generate energy to maintain ion gradients?

  • Substrate-level phosphorylation.

• Question 1: What enzyme is unique in the TCA cycle?

  • Succinate dehydrogenase

• Question 2: What is the effect of valinomycin and potassium ions on the proton motive force (PMF)?

  • PMF is reduced to zero.

• Question 3: How does dinitrophenol (DNP) uncouple oxidative phosphorylation?

  • Blocking proton transport.

• Question 4: Why might a 25-year old woman have chronic fatigue due to iron-deficiency anemia?

  • Iron's vital role in electron transfer in the electron transport chain is impaired.

• Question 5: What is a characteristic finding in OXPHOS diseases?

  • High NADH/NAD+ ratio in the mitochondria.

• Question 6: What protein complex is unaffected by lead poisoning interfering with heme synthesis?

  • Complex IV.

• Question 7: Rotenone inhibits NADH dehydrogenase. What's the effect on ATP production?

  • A 50% reduction in ATP production.

• Question 8: Which compound is a crucial component of oxidative phosphorylation?

  • ATP, which is produced through oxidative phosphorylation.

• Question 9: What component of the electron transport chain is lost when mitochondria are incubated with a high salt solution?

  • Cytochrome C

• Question 10: What could be a potential side effect of drugs that activate multiple uncoupling proteins (UCPs)?

  • Increased body temperature

• Question 1: What vitamin or enzyme cannot protect against free-radical damage?

  • Vitamin B6

• Question 2: What reaction is catalyzed by superoxide dismutase?

  • 2O2- + 2H+ → H2O2 + O2

• Question 3: How does vitamin E act as an antioxidant?

  • Vitamin E stabilizes free radicals by forming a covalent bond.

• Question 4: What metal can convert hydrogen peroxide to dangerous forms?

  • Iron.

• Question 5: Why is oxidative damage to mitochondrial DNA likely greater than nuclear DNA?

  • Mitochondrial membranes are permeable to reactive oxygen species (ROS).

• Question 6: What is the primary defect in chronic granulomatous disease?

  • Inability to generate superoxide

• Question 7: What process is impaired in patients with amyotrophic lateral sclerosis (ALS), possibly inherited from a father with ALS?

  • Detoxification of oxidized glutathione

• Question 8: How do compounds like nitroglycerin work, and what diseases can be affected by highly concentrated nitric oxide?

  • Form Nitric Oxide (NO), a vasodilator. They form reactive nitrogen-oxygen species (RNOS) which are involved in ischemic heart disease and infertility.

• Question 9: How can foreign compounds like alcohol increase the risk of free-radical injury?

  • Induction of enzymes like cytochrome P450.

• Question 10: Which food is high in antioxidants?

  • Citrus fruits.

• Question 1: What does liver glycogen degradation produce during glucagon release?

  • More glucose 1-phosphate than glucose.

• Question 2: What protein activity is impaired in a patient with abnormal glycogen branching patterns?

  • Glycogenin.

• Question 3: How does a deficiency in muscle phosphorylase affect exercising patients?

  • Patients exhibit decreased lactate levels in blood drawn from the forearm.

• Question 4: What process is likely enhanced in a normal glucose tolerance test?

  • Glycogen synthase activity.

• Question 5 (F): Why does glycogen degradation occur under high intracellular calcium levels when muscle protein kinase A is affected by cAMP?

  • Calcium is a secondary messenger independent of cAMP.

• Question 6: What is crucial for maintaining blood glucose levels?

  • Liver glucose-6-phosphatase

-Question 7: What is the correct statement about glycogen synthesis and degradation?

• Glycogen uses the same enzymes in both processes, meaning some steps are reversible.

• Question 8 (mutations): What is true about glycogen storage diseases (except type O)?

  • Type O is the only one that doesn't primarily affect the liver.

• Question 10 (newborn): What is most likely given to a newborn with glucose levels of 50 mg/dL in the first hour and 80 mg/dL two hours after delivery?

  • IV dextrose 50 to increase blood glucose.

Test your knowledge on endocrinology with this quiz focusing on diabetes, hormone functions, and metabolic processes. Questions cover various scenarios involving insulin, glucagon, and their effects on the body. Perfect for medical students and health professionals.