Questions DM
An 18-year-old man comes to the emergency department after feeling unwell for 5 days. Laboratory testing shows metabolic acidosis. His kidneys may respond to this in an effort to buffer urine pH by delivering ammonia to the urine. Which of the following compounds is most likely hydrolyzed to supply these proton acceptor molecules? 1. Glutamine 2. Aspartic acid 3. Histamine 4. 6-amino purine derivatives 5. Urea
1. Glutamine
An 18-year-old woman is evaluated for anemia. Lab tests show B12 deficiency, and macrocytic anemia. Which of the following laboratory findings would be present in this patient? 1. Increased FIGLU in urine 2. Decreased serum iron levels 3. Increased homocysteine levels 4. Decreased levels of serum folate 5. Increased levels of methylmalonate
3. Increased homocysteine levels 5. Increased levels of methylmalonate
Which molecule is most likely to be the major donor for the delivery of one carbon methylene units to THF? 1. Glutathione 2. S-adenosyl methionine 3. Serine 4. Thiamine 5. Uric acid 6. Adenosine triphosphate
3. Serine
A 34-year-old woman presents with macrocytic anemia and folate deficiency is confirmed by a lab test. Which of the following would most likely be impaired in this patient? 1. Conversion of homocysteine to cystathionine 2. Conversion of succinyl CoA to methylmalonyl CoA 3. Synthesis of thymidine monophosphate 4. Conversion of phenylalanine to tyrosine 5. Synthesis of creatines
3. Synthesis of thymidine monophosphate
A 4-day-old girl is admitted to the hospital because of a 2-day history of high fever and refusal to feed. Physical examination shows abdominal distention and meconium(first stool) coming from the vagina. Imaging studies show a connection between the rectum and the vagina. Which of the following is the most likely diagnosis? A. Anorectal agenesis B. Anal stenosis C. Membranous atresia D. Omphaloenteric fistula E. Duodenal stenosis F. Congenital megacolon
A. Anorectal agenesis (w/ a fistula) -urorectal septum got last
A 57-year-old man comes to the physician because of a 2-month history of productive cough and fever. Sputum culture is positive for tuberculosis. He is prescribed isoniazid. A vitamin is also prescribed to prevent the development of microcytic anemia. Which of the following enzymes most likely requires the coenzyme of this vitamin? A. ALA synthase B. ALA dehydratase C. Porphobilinogen deaminase D. Uroporphyrinogen synthase E. Ferrochelatase
A. ALA synthase
A research group investigates skeletal muscle glycogen phosphorylase and compares it to the liver isoform. Which one of the following molecules allosterically activates the muscle isozyme but not the hepatic isozyme? A. AMP B. Glucose 1-P C. Glucose 6-P D. Glucose E. Calcium
A. AMP
A 34-year-old-woman is diagnosed with cholelithiasis. What is responsible for this? A. Accumulations of cholesterol gall stones in the gallbladder B. increase of bile acids in the bile C. Decreased secretion of cholesterol into bile D. A deficiency of 7-Dehydrocholesterol reductase E. Decreased expression of HMG CoA reductase
A. Accumulations of cholesterol gall stones in the gallbladder
A 45-year-old woman comes to the physician for a routine examination. Her father and one of her siblings have type-2 diabetes mellitus. She is advised to fast overnight and come at 8AM the next day for the estimation of fasting blood glucose. Which of the following hepatic enzymes is most likely active at 8 AM? A. Carnitine palmitoyl transferase-I (CPT-I) B. Glycogen synthase C. Pyruvate kinase D. Phosphofructokinase-1 E. Glucokinase F. Acetyl CoA carboxylase
A. Carnitine palmitoyl transferase-I (CPT-I)
Thirty men between the ages of 25 and 30 years are recruited for a study of metabolism. They are all given a carbohydrate rich meal. After an hour, the insulin/glucagon ratio is elevated. Laboratory studies show increased de-novo synthesis of fatty acids and cholesterol in their livers. Which of the following enzymes is most likely used in both the pathways? A. Citrate lyase B. Acetyl CoA carboxylase C. HMG CoA synthase D. HMG CoA reductase E. Thiolase
A. Citrate lyase
A 75-year-old man comes to the emergency department because a 2-day history of nausea, vomiting, intense abdominal pain and inability to pass stool. He has had unintentional weight loss of 15 pounds over the last three months. Physical examination shows pale mucous membranes and a distended abdomen. Imaging studies show cancer of the colon extending from the left colic flexure to the middle of the descending colon. During the laparotomy, the surgeon observes abnormal omental metastasis along the greater curvature of the stomach. What is the most likely embryonic origin of the diseased omentum? A. Dorsal mesentery B. Ventral mesentery C. Midgut D. Hindgut E. Foregut
A. Dorsal mesentery
An abnormal cholesterol metabolism can lead to severe health problems. Which of the following statements correctly describes an event in cholesterol biosynthesis? During cholesterol synthesis, A. HMG CoA is converted to mevalonate in the rate limiting step. B. The cholesterol molecule formed is a straight chain hydrophilic molecule. C. The intermediate lanosterol is a 27C straight chain molecule. D. Squalene is converted directly into cholesterol. E. A reducing equivalent in form of NADPH is not required. F. Acetyl CoA is not required as a precursor.
A. HMG CoA is converted to mevalonate in the rate limiting step.
A 25-year-old woman presents to the emergency department with history of nauseas, vomiting and right sided shoulder pain, she was recently released from hospital after undergoing 14 days of antibiotics for a pelvic abscess. Vitals signs BP110/80,Pulse 100x1,Respiration rate 20x1,Temp 38.3 C. Physical examination reveals right sided chest tenderness around ribs 8-10.,there is also diffuse abdominal tenderness, muscle guarding and decreased bowel sounds. A CT scan of the abdomen shows an abnormal collection of fluid in the superior part of the right upper quadrant. In which of the following regions will the collection of fluid most likely be found? A. Hepato renal recess B. Subphrenic recess C. Left paracolic gutter D. Lesser sac E. Right paracolic gutter
A. Hepato renal recess
A healthy 25-year-old man is stranded in the mountains. He finds shelter and water, but no access to food. Nine days later he is rescued, hungry but unhurt. During this time, which amino acid was catabolized exclusively for ketone body synthesis? A. Lysine B. Isoleucine C. Tyrosine D. Glycine E. Pyruvate
A. Lysine (and Leucine)
A 54-year-old man is brought to the emergency department because of a sudden onset of severe abdominal pain. Laboratory studies show highly elevated serum lipase. Which of the following best describes the normal function of this enzyme? A. Needs bile salts for its activity B. Degrades triacylglycerol to free glycerol C. Cleaves after lysine or arginine residues D. Is proteolytically activated E. Is secreted by the bile duct
A. Needs bile salts for its activity (pancreatic lipase needs bile salts for activity and colipase to anchor it so you're able to break down TAG)
A 20-year-old woman is brought to the emergency department by her friends in an unconscious state. Her respirations are 30/min and are deep and rapid. Her breath test is positive for ethanol. Acid base studies show metabolic acidosis. The high NADH/ NAD+ ratio in hepatocytes is most likely responsible for her metabolic state. Which of the following reactions is most likely favored in her liver? A. Oxaloacetate to malate B. Pyruvate to acetyl CoA C. Pyruvate to oxaloacetate D. Oxaloacetate to phosphoenolpyruvate E. Lactate to pyruvate
A. Oxaloacetate to malate
A 56-year-old man came to emergency department because of intense abdominal pain and blood in his vomit. History reveals chronic peptic ulcer disease and non-compliance with prescribed diet and medication. Physical examination reveals pale mucous membranes and board like rigidity of the abdominal wall on superficial palpation. There is also rebound tenderness on deep palpation of the abdomen. Rectal examination shows "coffee ground" stool material on the gloved finger. Radiological examination show air under the left hemidiaphragm suggestive of a perforated duodenal ulcer. Which of the following arteries is the most likely source of the bleeding? A. Posterior superior pancreaticoduodenal B. Superior mesenteric C. Inferior mesenteric D. Posterior Inferior pancreaticoduodenal E. Right gastric
A. Posterior superior pancreaticoduodenal
During dissection of the thoracoabdominal cavity, thin nerves are seen originating from the thoracic sympathetic chain. These nerves synapse at the celiac ganglion. Which of the following best describes the fibres carried by these nerves? A. Preganglionic sympathetic and visceral pain fibers B. Postganglionic sympathetic and visceral pain fibers C. Preganglionic parasympathetic and visceral pain fibers D. Postganglionic sympathetic and somatic pain fibers E. Preganglionic sympathetic and somatic pain fibers
A. Preganglionic sympathetic and visceral pain fibers
A researcher investigates the synthesis of TAGs in fat cells under different experimental conditions. Which of the following is necessary for TAG synthesis in human adipocytes after a meal? A. Uptake of glucose with GLUT-4 into fat cells. B. Phosphorylation of free glycerol in adipocytes. C. A low insulin to glucagon ratio in the blood. D. Phosphorylation of hormone-sensitive lipase. E. Elevated epinephrine release.
A. Uptake of glucose with GLUT-4 into fat cells.
What is a lysosome? A. A cytoplasmic organelle which has pH environment of ~5 B. An organelle which contains degradative enzymes C. It removes cellular waste by breaking down biomolecules D. Contains enzymes synthesized in the rough endoplasmic reticulum E. Contains proteins with mannose-6-phosphate for cellular sorting
ALL THE ABOVE 😁
A researcher obtains a liver biopsy from a 37-year-old woman who has liver cancer. During laboratory analysis, which of the following enzymes has an activity that may allow formation of free ammonia? A. Alanine transaminase B. Aspartate transaminase C. Glutamate dehydrogenase D. Glutamine synthetase E. Asparagine synthetase
C. Glutamate dehydrogenase
A research group investigates the properties of the bifunctional enzyme which is found in liver, muscle and heart. What is the characteristic for the bifunctional enzyme found in hepatocytes that allows the switch from glycolysis to gluconeogenesis? A. A. It has two activities that follow each other. B. B. It is phosphorylated at low blood glucose C. C. It degrades fructose 1,6-bisP during fasting. D. D. It is not active after a meal. E. E. It has two genes one for each activity
B. B. It is phosphorylated at low blood glucose
A 2-year-old boy is brought to the physician by his mother because of a 1-month history of rough and scaly skin. Dietary history shows that he has been fed raw egg white for the past 6 months. A provisional diagnosis of biotin deficiency is made. Which of the following enzymes most likely requires this vitamin as a coenzyme? A. Fatty acid synthase B. Acetyl CoA carboxylase C. Pyruvate dehydrogenase D. Malic enzyme E. Citrate lyase
B. Acetyl CoA carboxylase
A researcher investigates substrates used in gluconeogenesis that are provided by the blood. Which one of the following descriptions is correct for the resulting fasting hepatic metabolism? A. Alanine activates pyruvate kinase. B. Alanine is used to form pyruvate by transamination. C. Glutamine is used to form dihydroxyacetone-P. D. Lactate and NADH are used to form pyruvate. E. Glycerol is used to form oxaloacetate.
B. Alanine is used to form pyruvate by transamination.
A 10-year-old girl is brought to the physician by her mother because of a life-long history of peculiar eating habits. She avoids fruits and foods containing table sugar. Laboratory studies show that after ingestion of such foods, she becomes hypoglycemic. As a child, she used to become drowsy and apathetic on ingesting such foods. Which of the following enzyme deficiency disorders is most likely in this patient? A. Galactose 1-phosphate uridyl transferase B. Aldolase B C. Fructose 1,6-bisphosphatase D. Fructokinase E. Lactase F. Galactokinase
B. Aldolase B
A research group investigates the regulated enzyme of hepatic de novo fatty acid synthesis. The assay conditions are optimized for maximal product formation. What activates this enzyme? A. Phosphorylation by AMPK B. Cytosolic citrate C. Palmitoyl CoA D. Cytosolic malonyl CoA E. Glucagon
B. Cytosolic citrate
A 50-year-old man is brought to the emergency because of severe left-sided chest pain that started 30 minutes ago. He has a 5-year history of poorly controlled diabetes mellitus. On physical examination, he has a body mass index of 32.Laboratory studies show his hemoglobin A1c to be 10%. Further investigations confirm diagnosis of myocardial infarction. What changes are associated with this condition? A. Increased hormone sensitive lipase activity B. Decreased lipoprotein lipase activity C. Decreased serum triacylglycerol D. Decreased serum LDL E. Increased serum HDL
B. Decreased lipoprotein lipase activity
The given image of the abdomen demonstrates a malignant pancreatic islet cell tumor of the pancreas near the junction of the pancreatic body and tail. The pancreatic islet cells involved with this tumor are derived from which of the following embryonic sources? A. Ectoderm B. Endoderm C. Somatic mesoderm D. Visceral mesoderm E. Neural crest
B. Endoderm
A 37-year-old man comes to the emergency department because of a 1-hour history of abdominal pain. He was punched in the stomach 90 minutes ago. Physical examination shows significant epigastric tenderness and abdominal guarding. Laboratory studies of the blood show elevated levels of amylase and lipase. Exploratory laparotomy shows a ruptured abdominal organ. Under normal physiological conditions, which of the following cells most likely produce the hormone that stimulate the release of the elevated enzymes in this patient? A. Enterocytes B. Enteroendocrine C. Parietal D. Goblet E. Zymogenic
B. Enteroendocrine
In a child with Fabry disease, which of the following compounds accumulates in the tissues? A. Ganglioside B. Globoside C. Heparan sulfate D. Dermatan sulfate E. Sphingomyelin F. Glycogen
B. Globoside
A 27-year-old man comes to the emergency department unresponsive after a motor vehicular collision. Vitals on admission BP:85/60, RR:20x1, PR:110x1. Fluid resuscitation was started with two large bore needle catheters placed in the antecubital fossa of his upper limbs. Ultrasound revealed "free" fluid (blood) in the peritoneal cavity. Follow up CT showed a laceration in the right lobe of the liver. Abdominal surgery was planned. Which of the following peritoneal ligaments will most likely be ligated during surgery to control the bleeding? A. Gastrocolic B. Hepatoduodenal C. Hepato gastric D. Gastrosplenic E. Coronary
B. Hepatoduodenal
A 32-year-old man comes to the emergency department unresponsive after a motor vehicular collision. Vitals on admission were BP:85/60, RR:20x1, PR:110x1. Fluid resuscitation was started with two large bore needle catheters placed in the antecubital fossa of his upper limbs. Physical examination shows extensive abdominal bruising in the right upper quadrant. Ultrasound revealed "free" fluid (blood) in the peritoneal cavity. Follow up CT shows a liver laceration and abdominal surgery was planned. Which of the following peritoneal ligaments was most likely ligated during surgery to control the bleeding? A. Gastrocolic B. Hepatoduodenal C. Hepato gastric D. Gastrosplenic E. Coronary
B. Hepatoduodenal
A 50-year-old woman comes to the clinic because of progressive increase in frequency of urination and poor vision for the past two years. Physical examination shows impaired sensation on the hands and feet. Laboratory studies reveals her hemoglobin A1c to 11.Urinalysis shows proteinuria but no ketonuria. What changes are responsible for these findings? A. Decreased sorbitol formation B. Increased non-enzymatic glycation of proteins C. Decreased activation of protein kinase C D. Increased formation of hexosamines E. Increased formation of DAG
B. Increased non-enzymatic glycation of proteins D. Increased formation of hexosamines E. Increased formation of DAG
A 3-year-old boy is brought to the physician by his parents because of a 4-month history of learning disability. Physical examination shows bilateral lens dislocation. Laboratory studies show elevated serum levels of a sulfur containing compound. Which of the following is most likely an additional complication of this disorder? A. Severe spinal arthritis B. Premature vascular disease C. Episodes of hyperammonemia D. Episodes of hypoglycemia E. Renal calcifications
B. Premature vascular disease in homocysteinuria
Docosahexaenoic acid (DHA) is important for brain functions and the visual cycle in the retina. Mammals lack the enzymes that can desaturate beyond the Δ9 position in the hydrocarbon chain during de novo synthesis of fatty acids. From which fatty acid is DHA synthesized in humans? A. Linoleic acid B. Linolenic acid C. Arachidonic acid D. Oleic acid E. Stearic acid
B. Linolenic acid
A 60-year-old man is admitted to the hospital for treatment of a posterior abdominal wall tumor that has resulted in lesions that have invaded the superior mesenteric periarterial plexus. Which of the following nervous pathways is most likely affected? A. Preganglionic parasympathetics to the posterior aspect of the stomach B. Post ganglionic sympathetics to the ascending colon C. Visceral afferents from the duodenal bulb D. Post ganglionic sympathetics from the descending colon E. Visceral afferents from the sigmoid colon
B. Post ganglionic sympathetics to the ascending colon -think around the arteries around stomach, so thing greater, lesser, least splanchnics. Superior mesenteric is a midgut artery, so that's postgang sympa with visceral afferent and pregang parasympathetic
A researcher isolates the rate limiting enzyme of cholesterol biosynthesis and the coenzyme required for its optimum activity. Which of the following coenzymes is most likely required for optimum activity of this enzyme? A. NADH B. NADPH C. Thiamine pyrophosphate D. Pyridoxal phosphate E. FADH2
B. NADPH; rate limiting enzyme is HMG CoA Reductase and needs Acetyl CoA and NADPH (E donor for all syntheses reactions from PPP)
A research group investigates a specific hepatic enzyme that catalyzes an irreversible step of gluconeogenesis and is not used in glycolysis. Which one of the following enzymes is investigated in this study? A. Bifunctional enzyme B. PEP carboxykinase C. Aldolase D. Glyceraldehyde 3P DH E. Phosphoglycerate kinase
B. PEP carboxykinase
A research group investigates the proteolytic activation of digestive enzymes in healthy volunteers. Which one of the following enzymes is synthesized as zymogen and performs autocatalytic activation at high proton concentration? A. Gastric lipase B. Pepsin C. Enteropeptidase D. Phospholipase A2 E. Trypsin
B. Pepsin A isn't synthesized as a zymogen and isn't autocatalytically activated, but loves high proton concentration with a low pH and released as active enzyme B performs autocatalytic activation with high levels of proteins at low pH. Comes from pepsinogen which is activated by hydrogen C is an enzyme activated by cholecystokinin (CCK) and recognizes only trypsinogen at neutral pH, only acts at the lumen of small intestine D is synthesized as pro enzyme and activated by trypsin; needs neutral pH E is active form of trypsinogen in the small intestine and needs a pH of 7-8 (neutral) so it can't do autocatylation
A breastfeeding 21-day-old infant was suddenly unable to hold down any milk after 3 weeks of normal feeding. In the pediatrician's office, the baby is obviously famished, presents with abdominal pain, appears slightly dehydrated, and has loose, watery stools. His mother nurses him in the office, and approximately 20 minutes later, the infant projectile vomits. The doctor notes the nonbilious and nonbloody vomitus. What is the most likely diagnosis for this infant? A. Esophageal atresia B. Pyloric stenosis C. Upper gastrointestinal (GI) bleed D. Lower GI bleed E. Intestinal obstruction
B. Pyloric stenosis
A 72-year-old man is brought to the emergency department because of a 1-hour history of severe abdominal pain. His blood pressure is 70/60mmHg, respiratory rate is 22/min and pulse is 100/min. Physical examination shows a pulsatile mass on superficial palpation of the abdomen. CT scan shows a large abdominal aortic aneurysm that includes the origin of the inferior mesenteric artery. During surgical repair of the aneurysm, the inferior mesenteric artery is sacrificed. Which of the following arteries would most likely provide collateral supply to the descending colon? A. Left gastroepiploic B. Right colic C. Splenic D. Superior rectal E. Inferior rectal
B. Right colic
A 22-year-old woman comes to the emergency department because of a 5-hour history of fever, nausea, vomiting and right sided shoulder pain. She was hospitalized for a pelvic abscess with accompanying peritonitis 14 days ago. She was treated with parenteral antibiotics and discharged from the hospital. Her blood pressure is 110/80mmHg, pulse is 100/min, respirations are 20/min and temperature is 38.1⁰C (100.6⁰F). Physical examination shows abdominal tenderness, decreased bowel sounds and right sided chest wall tenderness over the 8th to 11th ribs. A CT scan shows an abscess located in the right upper quadrant of her abdomen. In which of the following locations will this abscess most likely be found? A. Hepatorenal recess B. Subphrenic space C. Paracolic gutter D. Lesser sac E. Pleural sac
B. Subphrenic space
A 3-month-old boy is brought to the emergency department by his mother because of an 8-hour history of fever, vomiting and inconsolable crying. Physical examination shows abdominal distention and a red, swollen mass in the left inguinal/scrotal region. Radiographic imaging shows distended loops of bowel with entrapment of a segment of bowel represented in the image. Which of the following groups of lymph nodes most likely drains the entrapped segment of bowel? A. Celiac B. Superior mesenteric C. Inferior mesenteric D. Superficial inguinal E. Internal iliac
B. Superior mesenteric
A research group investigates a specific human glucagon receptor in the glucagon receptor family which is important in controlling blood glucose levels. This gene is found on chromosome 17 and a defect may cause non-insulin-dependent diabetes mellitus. Which tissue cells are used in this study? A. Skeletal myocytes B. Heart myocytes C. Hepatocytes D. Renal medulla cells E. Adipocytes
C. Hepatocytes
Twenty men aged 30-35 years old are recruited for a study of the gastric phase of digestion. They are all given a standard meal and the changes in the stomach are observed when food enters the stomach. Which of the following events is most likely observed during this phase? A. Chief cells release hydrochloric acid B. Activation of salivary amylase C. Activation of pepsinogen to pepsin D. Inhibition of lingual lipase E. Inhibition of gastric lipase
C. Activation of pepsinogen to pepsin
A UCD is suspected in a newborn infant due to elevated serum ammonia levels and high levels of circulating citrulline. Which enzyme is most likely to be deficient in this child? A. Carbamoyl Phosphate Synthetase I B. Ornithine Transcarbamoylase C. Argininosuccinate synthetase D. Argininosuccinate lyase E. Arginase
C. Argininosuccinate synthetase
A 31-year-old man has been diagnosed with acute fulminant hepatocellular failure. Which parameter would be raised in the blood of this patient? A. Blood urea nitrogen levels B. Blood creatinine levels C. Blood ammonia levels D. Blood albumin levels E. Blood uric acid levels
C. Blood ammonia levels
A 2-week-old girl is brought to the physician by her mother because of a 4-hour history of alternating seizures and hypotonia. A provisional diagnosis of an inborn error of amino acid metabolism. Oral thiamine supplementation is prescribed which alleviates the manifestations. Which of the following inherited enzyme deficiency disorders is most likely? A. Phenylalanine hydroxylase B. Homocysteine methyl transferase C. Branched chain alpha ketoacid dehydrogenase D. Homogentisate oxidase E. Methylmalonyl CoA mutase F. Medium chain acyl CoA dehydrogenase
C. Branched chain alpha ketoacid dehydrogenase
A 6-month-old boy is brought to the emergency department by his mother because of a sudden onset of seizures. The blood glucose level at the time of the seizure is 50 mg/dL. Hypoglycemia is observed a few hours following breast feeding. There is gross hepatomegaly and early signs of cataract formation. A provisional diagnosis of an enzyme deficiency disorder is made. Which of the following pathways is most likely directly affected in this patient? A. Muscle glycogenolysis B. Liver glycogenolysis C. Conversion of galactose to glucose D. Conversion of fructose to glycolytic intermediates E. Mitochondrial oxidation of fatty acids F. Digestion of lactose in the intestine
C. Conversion of galactose to glucose
I-cell disease is a lysosomal storage disease characterized by A. Benign clinical features B. Deficiency of one lysosomal enzyme C. Deficiency of the mannose 6-P marker D. Defective N-glycosylation E. Defective O-glycosylation
C. Deficiency of the mannose 6-P marker
A 2-year-old boy is brought to the physician by his mother because of a 3-month history of tripping over objects and developmental delay. Physical examination shows milestone developmental delay. Skin punch biopsy show abnormal lysosomes. Which of the following compounds is most likely accumulating in his lysosomes? A. Sphingomyelin B. Globoside C. Ganglioside D. Glycosaminoglycan E. Glycogen F. N-linked glycoprotein G. O-linked glycoprotein
C. Ganglioside
A researcher is studying regulation of metabolism that mimics a situation where there are elevated levels of AMP in hepatocytes. An enzyme involved in metabolism is inhibited under these conditions. Which of the following enzymes is most likely being studied by the investigator? A. Phosphofructokinase-1 B. Glycogen phosphorylase C. Fructose 1,6-bisphosphatase D. Pyruvate kinase E. AMP-kinase
C. Fructose 1,6-bisphosphatase
A-45-year-old man comes to the emergency department because of intense pain and bleeding in his rectum. Physical examination reveals an anal abscess located below the pectinate line. The patient is started on antibiotics and incision and drainage is planned. Which of the following lymph nodes were most likely enlarged in this patient? A. Vertical inguinal B. Para -aortic C. Horizontal inguinal D. Paralumbar E. Internal iliac
C. Horizontal inguinal
A 20-year-old woman comes to the physician because she is planning to reduce her weight. Her BMI is 30kg/m2. Laboratory studies show elevated levels of a hormone that is produced by adipose tissue and controls appetite. Which of the following hormones is most likely measured in this patient? A. Cholecystokinin B. Glucagon C. Leptin D. Ghrelin E. Insulin F. Adiponectin
C. Leptin
A 2-year-old boy is brought to the emergency room with cramping abdominal pain, fever, and vomiting. His parents say these symptoms began 12 hours ago and have progressively worsened. Abdominal radiology indicates a bowel obstruction that appears related to an abnormal intestinal outpocketing connected to the anterior abdominal wall. The consulting surgeon makes a diagnosis of Meckel diverticulitis and recommends surgery to resolve the problem. At which of the following sites does the surgeon expect to responsible for this condition? A. Lower duodenum B. Middle jejunum C. Lower ileum D. Cecum E. Transverse colon
C. Lower ileum
A 3-year-old girl has severe diarrhea which occurred in some of her playmates. She is treated at home with fluids and her physician recommends that her diet should be low in milk and fruits. Which of the following could be a clinical condition following her severe diarrhea? (3 choices) A. Congenital lactase deficiency B. Lactase nonpersistence C. Secondary lactose intolerance
C. Secondary lactose intolerance; diarrhea destroys intestine leading to loss of disaccharides A occurs at birth or shortly after B is a NO. Primary lactose intoloerance occurs later, the child has diarrhea with other playmates and diet is low in lactose and sucrose
A 43-year-old woman comes to the physician because of a 2-week history of lower abdominal pain. She has had previous surgeries for gallstones, perforated gastric ulcer and appendicitis. Physical examination shows a distended, painful abdomen with absent bowel sounds. Surgical exploration shows severe intestinal adhesion formation. Which of the following histological layers of the tubular GI tract was most likely damaged during her past surgeries resulting in these adhesions? A. Adventitia B. Muscularis mucosa C. Serosa D. Submucosa E. Muscularis externa F. Lamina propria
C. Serosa
A 34-year-old man comes to the emergency department because of a 3-day history of worsening nausea, vomiting, diarrhea and intermittent "colicky" abdominal pain. He has sickle cell anemia. Physical examination shows an ill-looking, dehydrated patient with a yellow tinge to the sclera, hepatomegaly and tenderness to the right upper quadrant on palpation. Laboratory studies of the blood show elevated total bilirubin and AST, ALT and ALP enzymes. He dies despite appropriate medical management. Liver biopsy grossly show brown pigments. Microscopic examination shows these to be iron storage complexes within the cytoplasm of Kupffer cells. Which of the following is the most likely location for these cells containing these iron complexes? A. Bile duct B. Cannaliculi C. Sinusoids D. Portal triad E. Perisinusoidal space
C. Sinusoids (lined by Kupffer cells) E would apply to Ito cells b/w hepatocytes and sinusoids B is found in tight junctions of hepatocytes D in portal areas A goes from cannaliculi to canals of herring
A pharmaceutical company develops a new drug and by law has to investigate any potential interactions between the new drug and grapefruit juice. Which one of the following conditions can occur when grapefruit juice is ingested by patients treated with statins? A. Statin release by the kidneys is increased. B. Statin degradation by Cytochrome P450 is increased. C. Statin blood levels increase to very high values. D. Statin uptake by intestinal epithelial cells is inhibited. E. Statin half-life in blood is decreased.
C. Statin blood levels increase to very high values.
A 60-year-old man is brought to the emergency department by his wife because of a 12-hour history of passing bloody stools. He is an alcoholic who has been previously treated for hemorrhoids and jaundice. Physical examination shows dilated veins radiating from his umbilicus. Rectal exam shows the stool contains bright red blood. The anastomosis of which of the following veins is most likely responsible for the patient's presenting complaint? A. Left gastric and esophageal B. Middle and inferior rectal C. Superior and middle rectal D. Inferior rectal and pudendal E. Paraumbilical and superficial epigastric
C. Superior and middle rectal
A 44-year-old man comes to the emergency department after receiving a gunshot wound to his abdomen. On admission, his vitals were: BP: 90/60, RR:20x1 PR:100x1, Oxygen saturation 94%in room air. The patient is stabilized with dressing to the wound, intravenous (IV) fluids and oxygen. Diagnostic studies show perforation of the small intestine. Surgery is planned to ligate the artery causing his blood loss. Which of the following arteries will most likely be ligated? A. Thoracic aorta B. Celiac C. Superior mesenteric D. Inferior mesenteric E. Common iliac
C. Superior mesenteric
A 6-month-old baby boy is treated in the hospital for his severe blisters all over his body, they are especially prevalent on his hands. His urine has a reddish color and contains high levels of uroporphyrin I and coproporphyrin I. Which one of following enzymes is deficient in his bone marrow? A. ALA synthase 2 B. Porphobilinogen deaminase C. Uroporphyrinogen III synthase D. Uroporphyrinogen decarboxylase E. Ferrochelatase
C. Uroporphyrinogen III synthase
The aspartate transaminase enzyme is purified from hepatocyte cells so that the reaction can be studied in-vitro. Which of the following best describes a characteristic of this reaction? A. Ammonia nitrogen may be fixed B. Ammonia nitrogen may be released C. a-ketoglutarate accepts a nitrogen D. a-ketoglutarate releases ammonia E. Thiamine pyrophosphate is a cofactor
C. a-ketoglutarate accepts a nitrogen
A 58-year-old man comes to the physician because of a 3-week history of yellow skin and sclera. He has a 10-year history of alcohol abuse. Physical examination shows scleral icterus. Liver biopsy shows tubulin damage. Which of the following molecules is most likely responsible for the biopsy findings? A. Acetate B. Ketone bodies C. Ethanol in mitochondria D. Acetaldehyde E. VLDL
D. Acetaldehyde
A researcher is using a primary hepatocyte cell culture to study gluconeogenesis in the fasting state. The cell culture is stimulated with glucagon and specific molecules are added which donate their carbon atoms to gluconeogenic pathway after stimulation. When labeled with unstable (radioactive) 14-C, which of the following molecules is best suited for this study? A. Palmitate B. Acetyl CoA C. Acetoacetate D. Aspartate E. Leucine
D. Aspartate
A 1st year medical student is presented with a slide taken from the tongue as part of a histology final exam. The associated question requires that he identify circumvallate papillae. Which of the following features would allowing to do so? A. Taste buds on dorsal surface of papillae B. Located on the lateral edge of the tongue C. Keratinized epithelium D. Associated with duct of von Ebner's glands
D. Associated with duct of von Ebner's glands
A research student isolates mitochondria of the hepatocytes. Which of the following enzymes are most likely localized to this organelle? A. Enzymes of oxidation of very long chain fatty acids B. Enzymes of TAG synthesis C. Enzymes of fatty acid biosynthesis D. Enzymes of beta-oxidation of fatty acids E. Enzymes of the pentose phosphate pathway F. Enzymes of glycolysis
D. Enzymes of beta-oxidation of fatty acids
Which of the following structures is a remnant of the embryonic ventral mesentery? A. Sigmoid mesocolon B. Mesentery of the small intestine C. Greater omentum D. Falciform ligament E. Transverse mesocolon
D. Falciform ligament
A 6-year-old girl is brought to the physician by her parents because of a 6-month history of poor feeding. The mother says that she likes to play with toys painted with lead-containing paint. Physical examination shows an irritable child with conjunctival pallor. Laboratory studies show low hemoglobin levels. Which of the following enzymes is most likely inhibited in this patient? A. Acetyl CoA carboxylase B. MethylmalonylCoA mutase C. Bilirubin UDP-glucuronyl transferase D. Ferrochelatase E. Hydroxymethylbilane synthase
D. Ferrochelatase
A 30-year-old woman comes to the physician because of a 4-month history of fatigue. Physical examination shows pallor. Laboratory studies show megaloblastic anemia and homocysteinemia. Additional studies show excessive excretion of formimino-glutamate (FIGLU) following histidine ingestion. Which of the following vitamins is most likely deficient in this patient? A. B6 B. B12 C. Biotin D. Folate E. Thiamine
D. Folate
A 1-year-old boy is brought to the physician by his parents for a follow-up examination. He is small for his age, with microcephaly and ambiguous genitalia. Targeted gene mutation analysis shows a pathologic variant in the gene encoding 7-dehydrocholesterol reductase. Which of the following pathways most likely requires this enzyme? A. Formation of mevalonate B. Formation of HMG CoA C. Formation of lanosterol D. Formation of cholesterol E. Formation of cholate
D. Formation of cholesterol
A mother brings in her 4-month-old baby boy to the family physician because he was less active and his body was limp and floppy which made it difficult for her to pick him up. The physician noted an enlarged liver during his physical exam of the abdomen. The laboratory tests show mild fasting hypoglycemia and elevated serum levels of ALT and AST. Further tests lead to the diagnosis of Cori disease. Which one of the following enzymes is deficient in this infant? A. Glucose 6-phosphatase B. Acid maltase C. Glycogen branching enzyme D. Glycogen debranching enzyme E. Hepatic glycogen phosphorylase
D. Glycogen debranching enzyme
A 9-year-old girl is brought to the physician by her parents because of a 2-week history of painful muscle cramps during exercise. Laboratory studies show normal plasma glucose level, but no increase of lactate in the blood following exercise. Inherited deficiency of which of the following is the most likely diagnosis? A. Carnitine palmitoyl transferase-II B. Glycogen debranching enzyme C. Glycogen branching enzyme D. Glycogen phosphorylase E. Pyruvate dehydrogenase complex
D. Glycogen phosphorylase
A 20-year-old woman comes to the physician for a follow-up examination. Her EKG is abnormal, and she is scheduled for a stress test for evaluation of her cardiac function. Which of her skeletal muscle enzymes is most likely phosphorylated by protein kinase A during the stress test? A. Glycogen phosphorylase B. Bifunctional enzyme C. Pyruvate dehydrogenase complex D. Glycogen phosphorylase kinase E. Pyruvate kinase
D. Glycogen phosphorylase kinase
In a child with Tay-Sachs disease, assay of enzyme activity is performed to confirm the diagnosis. Which of the following enzyme activities is lower in the child? A. β-glucosidase B. α-galactosidase C. Iduronidase D. Hexosaminidase A E. Iduronate sulfatase
D. Hexosaminidase A
A 60-year-old woman comes to the emergency department because of copious amounts of foul-smelling vomitus, diffuse crampy-like abdominal pain and shortness of breath. Her vitals on admission; BP: 85/60, PR:120x1, RR: 20x1 and O2 Saturation is 92% in room air. Physical examination reveals a globally distended abdomen with hyperactive (increased) bowel sounds. Imaging studies shows multiple distended loops of bowel secondary to an obstruction in the GI tract (see image provided). In which of the following locations will this obstruction most likely be found? A. Duodenojejunal flexure B. Transverse colon C. 1st part of duodenum D. Ileocecal valve E. Descending colon
D. Ileocecal valve (SBO)
Which of the following mitochondrial disorders can lead to progressive external ophthalmoplegia? A. MELAS B. LHON C. MERFF D. Kearns-Sayer E. Wet beriberi F. PDH deficiency
D. Kearns-Sayer
A 55-year-old man comes to the physician because of a 6-month history of gradually increasing fatigue and edema despite diuretic therapy. His supine blood pressure is 95/48 mmHg. Physical examination shows dependent edema to the mid-thigh and fine crepitations at the base of the lungs. Laboratory studies show impaired renal function. Imaging studies shows globally decreased blood flow including to the GI arteries resulting in generalized ischemia. Which part of the colon will most likely show the greatest amounts of ischemic changes? A. Cecum B. Ascending colon C. Right colic flexure D. Left colic flexure E. Transverse colon
D. Left colic flexure (think watershed area)
A researcher is observing liver metabolism in the well-fed state in experimental animals. It is observed that fatty acid synthesis is active, and the newly synthesized fatty acids are not metabolized by β-oxidation. Which of the following molecules most likely inhibits the hepatic carnitine shuttle during the observation period? A. Palmitoyl CoA B. Long chain fatty acyl CoA C. Acetyl CoA D. Malonyl CoA E. HMG CoA
D. Malonyl CoA
Pyruvate + NAD+ + CoA ⇒ AcetylCoA + NADH + CO2The above reaction shown above takes place in which cellular compartment? A. Cell membrane B. Cytoplasm C. Golgi D. Mitochondria E. Nucleus
D. Mitochondria
A 35-year-old man comes to the physician because of a 3-month history of burning pain in the epigastric region. Endoscopy shows an ulcer in the posterior wall of the stomach. Biopsy of the area shows the presence of H. Pylori. Which of the following therapies would most likely be prescribed? A. H2 blocker and proton pump stimulator B. Proton pump stimulator and antibiotics C. Gastrin stimulator and proton pump inhibitor D. Proton pump inhibitor and antibiotics
D. Proton pump inhibitor and antibiotics
A 24 year old female presents to the emergency department with complaint of lower abdominal pain since 4 hours duration, physical examination reveals tenderness in the left iliac region, a negative pregnancy test rules out ectopic pregnancy and an abdominopelvic ultrasound is ordered which shows the presence of a large cyst on the left ovary. Which of the following is the most likely location for the pooling of content from this cyst? A. Hepatorenal recess B. Right Paracolic gutter C. Lesser sac D. Rectouterine pouch
D. Rectouterine pouch
A 53-year-old man who is a known alcoholic is brought to the ER by the police because he exhibits abnormal behavior. Lab tests show a vitamin B1 deficiency. Which enzyme was most likely analyzed to reveal the vitamin deficiency in this patient? A. Pyruvate DH B. Alpha KG DH C. BC alpha keto acid DH D. Transketolase E. Glutamate DH F. Glutaminase
D. Transketolase A & B would be muscle biopsies with C being a liver biopsy. D would come straight from the blood
A 14-year-old boy is brought to the physician by his parents because of a 3-week history of muscle cramps. Muscle biopsy shows normal glycogen levels, but increased TAG droplets. His plasma glucose and ketone body levels are within normal limits. Which of the following processes is most likely defective in this patient? A. Oxidation of very long chain fatty acids B. Oxidation of branched chain fatty acids C. Muscle glycogenolysis D. Transport of fatty acids into mitochondria E. Endothelial lipoprotein lipase activity F. Adipose tissue lipolysis
D. Transport of fatty acids into mitochondria
A 9-month-old boy is brought to the emergency department by his parents because of a sudden-onset of seizures. Physical examination shows hepatomegaly. Imaging studies show bilateral enlargement of the kidneys. Laboratory studies are shown in the table. Which of the following disorders is most likely? A. Medium chain acyl CoA dehydrogenase (MCAD) deficiency B. Myopathic carnitine deficiency C. Carnitine Palmitoyl Transferase-II (CPT-II) deficiency D. von Gierke disease E. McArdle disease
D. von Gierke disease
A 57-year-old man has his annual health evaluation. His serum cholesterol levels are elevated, and the physician prescribes statins. This drug inhibits the regulated enzyme of cholesterol synthesis. What is Characteristic of this enzyme? A. It is activated at high cytosolic cholesterol B. It is activated by AMP C. It uses NAD+ as coenzyme D. It is activated by phosphorylation E. It uses cytosolic HMG CoA as substrate
E. It uses cytosolic HMG CoA as substrate
You are explaining to your junior colleague that excessive cytosolic concentrations of the activated 16 C product of hepatic fatty acid biosynthesis inhibits the regulated enzyme of the pathway. What is the name of the regulated enzyme of the pathway? A. Elongase B. Citrate lyase C. Citrate synthase D. Fatty acid synthase E. Acetyl CoA carboxylase
E. Acetyl CoA carboxylase
A scientist is studying nitrogen metabolism and identifies an enzyme which catalyzes the exchange of the nitrogen from glutamate to oxaloacetate. Which of the following proteins is most likely responsible for this catalytic activity? A. Glutaminase B. Glutamine synthetase C. Asparaginase D. Glutamate dehydrogenase E. Aspartate aminotransferase F. Alanine transaminase
E. Aspartate aminotransferase
A 2-month-old baby is brought to the family physician by his mother due to the baby's excessive crying, vomiting and weak musculature. The infant has a history of developmental delay. His blood has high levels of lactate and alanine. Further investigations include a biopsy of his hepatic tissue which indicates deficiency of pyruvate carboxylase. What is the normal function of this enzyme? A. It forms acetyl CoA in mitochondria. B. It forms an inhibitor of the TCA cycle. C. It forms an activator of pyruvate kinase. D. It forms phosphoenolpyruvate in cytosol. E. It forms oxaloacetate in mitochondria.
E. It forms oxaloacetate in mitochondria.
Twenty men aged 18-19 years are recruited for a metabolic study. They are all given a breakfast consisting of pancakes and maple syrup. Two hours later, they are asked to run a mile. Laboratory studies show elevated levels of epinephrine and norepinephrine levels in the participants. Which of the following molecules most likely acts as an allosteric inhibitor of hepatic PFK-1 during the sympathetic response in these individuals? A. Acetyl CoA B. Palmitoyl CoA C. Adenosine monophosphate D. Glucose 1-phosphate E. Citrate
E. Citrate
A research group investigates the effects of dietary intake of ethanol in humans. Which one of the following descriptions is found in their publication? A. Ethanol inhibits absorption of ethylene glycol. B. Ethanol absorption is best on full stomach. C. Ethanol is used by MEOS to form acetate in cytosol. D. Ethanol cannot be metabolized in the brain. E. Ethanol metabolism changes the NADH/NAD+ ratio.
E. Ethanol metabolism changes the NADH/NAD+ ratio
A 32-year-old man is brought to the emergency department by paramedics after a car crash in an unresponsive state. Fluid resuscitation is started with two large bore needle catheters placed in the antecubital fossa of his upper limbs. Physical examination shows extensive abdominal bruising in the right upper quadrant. Imaging studies of the abdomen show blood in the peritoneal cavity and liver laceration. Abdominal surgery is planned. Which of the following peritoneal ligaments is most likely ligated during surgery to control the bleeding? A. Gastrocolic B. Gastrophrenic C. Hepatogastric D. Gastrosplenic E. Hepatoduodenal
E. Hepatoduodenal
A 2-year-old girl is treated with IV infusion therapy with iduronidase. She likely has which of the following disorders? A. Gaucher Disease B. Hunter Syndrome C. Tay-Sachs Disease D. Niemann-Pick Disease E. Hurler Syndrome
E. Hurler Syndrome
A 72-year-old man comes to the emergency department because of nausea, vomiting, intense abdominal pain and changes in his bowel habits for the last two days. His vitals on admission were: BP 160/90, PR:90x1 RR: 16x1, Oxygen saturation 96 % in room air. Physical examination shows pale mucous membranes and a left sided tender abdominal mass. Laboratory test show anemia and the presence of occult blood in his stool. Barium enema shows an obstructive mass in the descending colon . Which of the following lymph nodes will most likely be enlarged on physical examination? A. Celiac B. Superior mesenteric C. Right supraclavicular D. Inferior mesenteric E. Left supraclavicular
E. Left supraclavicular
A 50-year-old woman comes to the emergency department because of a 1-day history of fever and intense right lower abdominal pain. Physical examination shows guarding in the right lower abdominal quadrant accompanied by rebound tenderness at McBurney's point. Imaging studies show free fluid in the abdominal cavity. A diagnosis of a ruptured appendix is made. Which of the following nerve fibers most likely carries the visceral afferents responsible for the transmission of pain sensation from the affected organ? A. Vagus B. Greater thoracic splanchnics C. Pelvic splanchnics D. Lumbar splanchnics E. Lesser thoracic splanchnics
E. Lesser thoracic splanchnics
A 50-year-old woman comes to the emergency department because of a 1-day history of fever and intense right lower abdominal pain. Physical examination shows guarding in the right lower abdominal quadrant accompanied by rebound tenderness at McBurney's point. Imaging studies show free fluid in the abdominal cavity. A diagnosis of a ruptured appendix is made. Pain fibers from which of the following organs most likely travel back to the spinal cord with the same type of nerve fibers as the affected organ? A. Cervix B. Upper vagina C. Anal opening D. Lower vagina E. Ovary
E. Ovary (everything else is too low in position and below the PPL with C & D below pelvic diaphragm compared to where the appendix is)
A woman brings her 4-year-old daughter to the pediatrician because of continuing problems with vomiting, constipation, and abdominal distension. Extensive examination results in a diagnosis of an aganglionic colon. The girl has a deficiency in which of the following neural cell types? A. Pseudounipolar sensory neurons B. Presynaptic sympathetic neurons C. Presynaptic parasympathetic neurons D. Postsynaptic sympathetic neurons E. Postsynaptic parasympathetic neurons
E. Postsynaptic parasympathetic neurons
A research group investigates heme synthesis and possible enzyme defects which could lead to colored abnormal intermediates. Which of the following molecules is the only normal intermediate in heme synthesis which has a red color? A. Porphobilinogen B. Hydroxymethylbilane C. Uroporphyrinogen III D. Coproporphyrinogen III E. Protoporphyrin IX
E. Protoporphyrin IX
A 22-year-old woman comes to the emergency department because of fever, nausea, vomiting and right sided shoulder pain. Patient history reveal hospitalization with parenteral antibiotics 14 days ago for a pelvic abscess. Today on admission her vitals are BP: 110/80, PR:100x1. RR:20x1, Temperature:38.1⁰C (100.6⁰F). Physical examination shows right sided chest wall tenderness over the 8th to 11 ribs. There is also diffuse abdominal tenderness, muscle guarding and decreased bowel sounds. CT scan of the abdomen shows an abnormal collection of fluid in the superior part of the right upper quadrant. The surgeon suspects an abscess secondary to the primary infection found in pelvis 14 days ago. Which of the following most likely provided the pathway for the spread of infection? A. Omental foramen B. Lesser omentum C. Left paracolic gutter D. Lesser sac E. Right paracolic gutter
E. Right paracolic gutter
The TCA cycle reaction most similar to PDH reaction which converts pyruvate to acetyl CoA is the conversion of: A. Citrate to isocitrate B. Fumarate to malate C. Malate to oxaloacetate D. Succinyl CoA to succinate E. a-ketoglutarate to succinyl CoA
E. a-ketoglutarate to succinyl CoA
A 35-year-old man comes to the emergency department because of a 2-hour history of epigastric abdominal pain that radiates to the back. His blood pressure is 100/60mmHg, respirations are 21/min and pulse is 100/min. Physical examination shows a diaphoretic patient with abdominal wall guarding and rebound tenderness. Laboratory studies show elevated serum lipase and amylase. Which of the following nerves most likely carries the pain fibers from the affected organ back to the spinal cord? A. Lumbar splanchnics B. Vagus C. Pelvic splanchnics D. Lesser thoracic splanchnics E. Least thoracic splanchnics F. Great thoracic splanchnics G. Subcostal H. Intercostal
F. Great thoracic splanchnics
A 60-year-old man is brought to the emergency department by his wife because of a 2-hour history of vomiting blood. He has 10-year history of alcoholism and has been previously treated for hemorrhoids and jaundice. Physical examination shows varicosities on his anterior abdominal wall radiating from his umbilical area. The anastomosis of which of the following veins is most likely responsible for the appearance of his abdominal wall? A. Superior and inferior epigastric B. Splenic and left gastric C. Portal and inferior vena cava D. Esophageal and inferior vena cava E. Esophageal and left gastric F. Paraumbilical and superficial epigastric
F. Paraumbilical (portal) and superficial epigastric (caval); left gastric (portal) is responsible for vomiting; superior rectal (portal) and inferior& middle rectal (caval) responsible for hemorrhoids
A researcher studying flux of nitrogen containing molecules in human cells isolates an enzyme that either releases or fixes NH3 depending on the relative concentration of substrates. Which of the following enzymes is most likely being studied? A. Alanine transaminase B. Glutaminase C. Asparagine synthetase D. CPS1 E. OTC F. ASS G. Glutamate dehydrogenase H. BCAA dehydrogenase complex
G. Glutamate dehydrogenase
