Question 1

As a hypothetical approach to treating the hyperglycemia associated with Type 2 diabetes, a drug firm proposes to develop an inhibitor of liver glycogen phosphorylase. What is the biochemical rationale for this approach to inducing hypoglycemia?

A) hepatic fatty acid oxidation will decrease leading to reduced energy production needed for gluconeogenesis
B) hepatocytes will have a reduced capacity to store glucose following meals
C) liver glucose output will be reduced early during fasting
D) the resultant increase in glycogen storage will inhibit glucose uptake by the liver leading to increased utilization in skeletal muscle
E) there will be an increase in hepatic gluconeogenesis

liver glucose output will be reduced early during fasting

Accepted Answer

Inhibiting liver glycogen phosphorylase would reduce the breakdown of glycogen into glucose, thereby decreasing liver glucose output during fasting, which could help lower blood glucose levels.  During early fasting, as the level of glucose in the blood falls, the pancreas releases glucagon into the circulation to counter this drop. The major site of glucagon action is the liver. There it induces the activity of the glycogen phosphorylase leading to an increase in glucose release from glycogen stores. Thus, an inhibition of glycogen phsphorylase would limit the ability of the liver to provide glucose to the blood. Negatively affecting the activity of glycogen phosphorylase would not significantly affect the rate of hepatic fatty acid oxidation, skeletal muscle glucose usage, nor hepatic gluconeogenesis.

Question 2

In Type 1 diabetes there is an associated hyperlipidemia. The best explanation for this is that the level of an enzyme important for fat homeostasis is reduced. Which of the following is this enzyme?&#10;A) acyl-CoA dehydrogenase (eg, MCAD)&#10;B) carnitine palmitoyltransferase I&#10;C) glucose 6-phosphatase&#10;D) hepatic lipase&#10;E) lipoprotein lipase

Accepted Answer

Lipoprotein lipase is responsible for breaking down triglycerides in lipoproteins into free fatty acids, and its activity is reduced in Type 1 diabetes, leading to hyperlipidemia. One of the effects of insulin is to increase the level of lipoprotein lipase (LPL) expression in endothelial cells. The lack of normal levels of circulating insulin in Type 1 diabetics results in impaired regulation of LPL levels. Reduced LPL contributes to the hyperlipidemia associated with T1D.

Question 3

Obesity, genetic profile, and aging all contribute to the development of Type 2 diabetes. Of the following, which is the most important additive factor for these 3 conditions in the development of Type 2 diabetes?

A) elevated hepatic ketogenesis
B) elevated pancreatic glucagon secretion
C) impaired renal clearance of glucose
D) increased adipose tissue activity leading to hyperlipidemia
E) muscle resistance to insulin

muscle resistance to insulin

Accepted Answer

Muscle resistance to insulin is a key factor in the development of Type 2 diabetes, as it directly affects the body's ability to utilize glucose, leading to elevated blood sugar levels. The influence of obesity, genetic profile, and age on overall metabolism is most significant at the level of skeletal muscle sensitivity to the actions of insulin. Due to the overall mass of skeletal muscle in the body, the uptake of glucose by this tissue, and consequently its role in blood glucose homeostasis, is a significant factor in insulin responses. Progressive loss of skeletal muscle sensitivity to insulin leads to increased rates of visceral cell lipolysis and pancreatic b-cell compensation. Eventually, the pancreas can no longer continue compensating for impaired insulin responses and pancreatic b-cell decompensation occurs, further exacerbating the problem. The disrupted insulin response leads to increased hepatic gluconeogenesis, which further increases circulating glucose levels. The overall outcome of these responses is development of progressively worsening Type 2 diabetes.

Question 4

The sulfonylurea class of drugs used to treat Type 2 diabetes function by which of the following mechanisms?&#10;A) activating the PPARg class of factors leading to increased hepatic glucose metabolism&#10;B) binding to and blocking pancreatic K+ channels leading to increased insulin secretion&#10;C) interfering with carbohydrate digestion, thus reducing glucose intake&#10;D) restricting hepatic glucose output, thereby reducing the hyperglycemia&#10;E) stimulating pancreatic glucose metabolism leading to increased insulin secretion

Accepted Answer

Sulfonylureas function by binding to and blocking ATP-sensitive potassium channels on pancreatic beta cells, which leads to depolarization and increased insulin secretion. The sulfonylurea drugs function by binding to and inhibiting the pancreatic ATP-dependent K+ channel (KATP) that is responsible for glucosemediated insulin secretion. The normal pancreatic response to increased blood glucose is an increased uptake by b-cells with concomitant oxidation. The increase in glucose oxidation leads to an elevation in the ATP:ADP ratio. This in turn leads to an inhibition of the KATP channel. The net result is a depolarization of the cell leading to Ca₂₊ influx and insulin secretion.

Question 5

Numerous pharmacological agents are currently being used in the clinic as a means to reduce the hyperglycemia associated with Type 2 diabetes. Which of the following class of compounds exerts a portion of their effects by activating the metabolic master regulator, AMPK?

A) biguanides (eg, Metformin)
B) a-glucosidase inhibitors (eg, Precose)
C) GLP-1 mimetics (eg, Byetta)
D) meglitinides (eg, Prandin)
E) sulfonylureas (eg, Glipizide)

Accepted Answer

Biguanides, such as Metformin, exert their effects in part by activating AMPK, which helps to improve insulin sensitivity and reduce hepatic glucose production. Metformin exerts part of its effects by modulating mitochondrial activities. Metformin has a mild inhibitory effect on complex I of oxidative phosphorylation, has antioxidant properties, and activates both glucose-6-phosphate dehydrogenase, G6PDH and AMPK. The importance of AMPK in the actions of metformin stems from the role of AMPK in the regulation of both lipid and carbohydrate metabolism. The activation of AMPK by metformin is likely related to the inhibitory effects of the drug on complex I of oxidative phosphorylation. This would lead to a reduction in ATP production and, therefore, an increase in the level of AMP and as a result activation of AMPK.

Question 6

The Randle hypothesis was proposed to explain the acquisition of insulin resistance associated with central adiposity. Which of the following statements best reflects the basis of the Randle hypothesis?

A) an increase in adipocyte volume due to increased lipid storage causes adipocytes to lose their responsiveness to insulin
B) increased circulating free fatty acids in obese individuals impair the ability of insulin to stimulate skeletal muscle cell glucose uptake
C) long-term hyperlipidemia leads to permanent elevation in pancreatic insulin secretion that ultimately causes downregulation of insulin receptors
D) the high level of circulating free fatty acids stimulates the liver to shut off gluconeogenesis that then impairs pancreatic sensing of the need for insulin release
E) the hyperglycemia prevalent in obese individuals activates insulin release from the pancreas leading to increased adipocyte lipolysis

Accepted Answer

The Randle hypothesis suggests that increased circulating free fatty acids in obese individuals impair insulin's ability to stimulate glucose uptake in skeletal muscle, contributing to insulin resistance.  The Randle hypothesis states that elevations in circulating free fatty acids (FFAs) interfere with insulin action in liver and skeletal muscle. Increased FFA uptake and metabolism by the liver results in an increased production of acetyl-CoA. All of the acetylCoA cannot be oxidized completely in the TCA cycle. The elevated acetyl-CoA levels result in inhibition of pyruvate dehydrogenase resulting in increased citrate transport to the cytosol. Increased cytosolic citrate inhibits 6-phosphofructokinase-1 (PFK1) resulting in reduced glucose oxidation and an increase in glucose- 6-phosphate levels. Increases in glucose 6-phosphate lead to inhibition of skeletal muscle hexokinase resulting in reduced glucose utilization. In addition, the elevated plasma FFAs impair insulin receptor tyrosine phosphorylation of IRS1 resulting in defects in insulinmediated signaling events in target cells, primarily skeletal muscle. Loss of insulin signaling in skeletal muscle prevents glucose transporter (GLUT4) mobilization to the cell surface with a resultant block to glucose uptake. The overall consequences of a high-fat diet are a progressive impairment in hepatic glucose homeostasis, impairment of insulin-mediated glucose uptake by skeletal muscle, and pancreatic b-cell decompensation. The latter leads to reduced insulin secretion and, thus, further impairment of the role of insulin in regulation of blood glucose.

Question 7

Patients with poorly controlled diabetes have elevated levels of blood glucose. One severe consequence of the hyperglycemia is an increase in glucose attachment to serum proteins. Which of the following proteins, when glycosylated, is an excellent measure of the length of time someone has sufferred from an episode of hyperglycemia?

A) albumin
B) cholesterol
C) fatty acids
D) hemoglobin
E) transferrin

Accepted Answer

Hemoglobin, when glycosylated, forms HbA1c, which reflects average blood glucose levels over the past 2-3 months, making it an excellent measure of long-term glucose control in diabetes. Assessment of therapeutic management of the hyperglycemia in T2D is accomplished by routine measurement of the circulating levels of glycosylated hemoglobin, designated as the level of HbA1c, often designated as just A_1C. Since hemoglobin is present in red blood cells and these cells have a limited life span of 120 days in the circulation, measurement of HbA_1c levels is a relatively accurate measure of the amount of glucose in the blood and the length of time the level has been elevated.

Question 8

Type 1 diabetes is most often characterized by which of the following?&#10;A) decreased glucagon secretion leading to hyperlipidemia&#10;B) decreased insulin receptor response to insulin binding&#10;C) elevated fatty acid oxidation leading to ketonemia&#10;D) elevated insulin secretion leading to severe hypoglycemia&#10;E) impaired glucagon-dependent inhibition of glycolysis leading to hyperglycemia

Accepted Answer

Type 1 diabetes is characterized by the autoimmune destruction of insulin-producing beta cells in the pancreas, leading to insufficient insulin production. This results in elevated fatty acid oxidation and ketone body production, causing ketonemia.  The most frequent consequence of poorly controlled T1D is ketoacidosis, referred to as diabetic ketoacidosis, DKA. The hyperketonemia in DKA is the result of insulin deficiency and unregulated glucagon secretion from a-cells of the pancreas. Circulating glucagon stimulates the adipose tissue to release fatty acids which are taken up and oxidized, primarily by the liver. Under these conditions, the level of fatty acid oxidation is in excess of the livers' ability to fully oxidize the excess acetyl-CoA and, thus, the compound is diverted into ketones synthesis. The ketones are released into the circulation and because they are acidic lower the pH of the blood resulting in metabolic acidosis.

Question 9

An investigational diabetes treatment involving a hypoglycemia-inducing drug has been developed. This drug is designed to inhibit dipeptidylpeptidase IV (DPP4) activity and has been shown to decrease plasma glucose concentration and pancreatic glucagon secretion. DPP4 hydrolyzes which of the following hormones such that its inhibition results in the observed effects?

A) glucagon
B) glucagon-like peptide-1 (GLP-1)
C) glucose-dependent insulinotropic peptide (GIP)
D) insulin
E) prohormone convertase-2/3

Accepted Answer

DPP4 hydrolyzes glucagon-like peptide-1 (GLP-1), which stimulates insulin secretion and inhibits glucagon secretion. Inhibition of DPP4 results in increased GLP-1 levels, which leads to decreased plasma glucose concentration and pancreatic glucagon secretion.  GLP-1 stimulates postprandial insulin secretion and has also been shown to stimulate proliferation and inhibit apoptosis of pancreatic β-cells. GLP-1 also inhibits glucagon release from pancreatic α-cells, inhibits gastric emptying, and reduces food intake. DPP4 is involved in the degradation of GLP-1, thus DPP4 inhibitors act to prevent inactivation of and prolong the duration of action of GLP-1.

Question 10

Which of the following would be evident in Type 1 diabetes?&#10;A) decreased glucagon secretion leading to hyperlipidemia.&#10;B) decreased insulin receptor response to insulin binding.&#10;C) elevated glucagon secretion leading to hyperlipidemia.&#10;D) elevated insulin secretion leading to severe hypoglycemia.&#10;E) impaired glucagon-dependent inhibition of glycolysis leading to hyperglycemia

Accepted Answer

In Type 1 diabetes, there is an absolute deficiency of insulin due to autoimmune destruction of pancreatic beta cells. This leads to elevated glucagon secretion, which contributes to hyperlipidemia and hyperglycemia.  In addition to the loss of insulin secretion by β-cells of the pancreas in T1D, the function of a-cells is also abnormal. There is excessive secretion of glucagon in T1D patients. Normally, hyperglycemia leads to reduced glucagon secretion. However, in patients with T1D, glucagon secretion is not suppressed by hyperglycemia. The resultant inappropriately elevated glucagon levels exacerbate the metabolic defects due to insulin deficiency.

Question 11

Type 2 diabetes can best be characterized as which of the following?&#10;A) adequate insulin secretion coupled to impaired postreceptor responses&#10;B) being caused by autoimmune destruction of pancreatic b-cells&#10;C) correlated to disruptions in glucagon secretion&#10;D) lack of insulin receptors on hepatocyte&#10;E) resulting in frequent episodes of ketoacidosis

Accepted Answer

The answer of Type 2 diabetes can best be characterized...

Question 12

Type 1 diabetes is highly associated with the inheritance of specific alleles of genes in the MHC cluster as well as other unrelated loci. Which of the following polymorphic alleles is most highly associated with the potential for the development of Type 1 diabetes?

A) a VNTR in the 5′ region of the insulin gene
B) glutamic acid decarboxylase 2 (GAD2)
C) HLA-B27
D) HLA-DQ
E) HLA-DR3

Accepted Answer

The answer of Type 1 diabetes is highly associated with...

Question 13

The occurrence of type 2 diabetes (T2D) in adolescent females can lead to the development of polycystic ovarian syndrome (PCOS). PCOS is the result of follicular atresis and ovulatory dysfunction brought about by a hyper-androgenic microenvironment in the ovary. Which of the following statements reflects the underlying cause of the hyperandrogenic state in females with T2D?

A) hyperinsulinemia, associated with T2D, reduces the level of sex hormone-binding globulin leading to increased free testosterone.
B) T2D in adolescents is primarily the result of obesity and the associated disruption in fatty acid metabolism negatively affects adrenal estrogen production.
C) the increased level of circulating lipid in T2D patients competes for steroid binding to sex hormone-binding globulin resulting in a reduced transport of estrogen within the ovary.
D) the persistent hyperglycemia associated with T2D causes increased levels of glycosylated hemoglobin, which interferes with the need for increased ovarian vascularization at puberty

Accepted Answer

The answer of The occurrence of type 2 diabetes (T2D)...

Question 14

Metformin is one of the most prescribed hypoglycemia-inducing drugs in the treatment of Type 2 diabetes. One of the effects of metformin is a reduction in adipose tissue lipolysis which is affected via the activation of AMP-activated kinase (AMPK). Which of the following actions of AMPK explains the adipose tissue benefits of metformin?

A) activation of acetyl-CoA carboxylase
B) activation of fatty acid synthase
C) inhibition of hormone sensitive lipase
D) inhibition of mammalian target of rapamycin, mTOR
E) inhibition of 6-phosphofructokinase 2, PFK2

Accepted Answer

The answer of Metformin is one of the most prescribed...

Question 15

Hemoglobin is nonenzymatically glycosylated as glucose enters erythrocytes. Because erythrocytes routinely die and are replaced, the level of glycosylated hemoglobin is a good measure of the length of time glucose levels were elevated. Diabetic patients are most familiar with this process because they routinely measure for which of the following?

A) HbA_1c
B) HbA₂
C) HbC
D) HbG
E) HbS

Accepted Answer

The answer of Hemoglobin is nonenzymatically glycosylated as glucose enters...

Question 16

In Type 1 diabetes, the increased production of ketone bodies is primarily a result of which of the following?&#10;A) a substantially increased rate of fatty acid oxidation by hepatocytes&#10;B) an increase in the rate of the citric acid cycle&#10;C) decreased cyclic AMP levels in adipocytes which causes accelerated fatty acid release&#10;D) elevated acetyl-CoA levels in skeletal muscle driving ketone body synthesis&#10;E) increased hepatic glucose release from glycogen driving acetyl-CoA production

Accepted Answer

The answer of In Type 1 diabetes, the increased production...

Question 17

You are carrying out studies with a drug to potentially treat the hyperglycemia of Type 2 diabetes. Your studies find that in cell culture this drug induces the activity of peroxisome proliferatoractivated receptor-g (PPARg). These results indicate that your experimental drug is most likely related to which of the following class of hypoglycemia-inducing drugs already in clinical use?

A) biguanides
B) meglitinides
C) sulfonylureas
D) thiazolidinediones

Accepted Answer

The answer of You are carrying out studies with a...

Question 18

The drug metformin is an effective treatment for the hyperglycemia associated with diabetes. One of the major sites of action for metformin is the liver and its use is ideal for obese patients and for younger Type 2 diabetics with normal liver function. Given that the drug lowers circulating levels of glucose, which of the following hepatic enzymes is most likely activated as a consequence of metformin administration?

A) AMP-activated protein kinase (AMPK)
B) glycogen phosphorylase
C) 6-Phosphofructo-1-kinase (PFK-1)
D) phosphoenolpyruvate carboxykinase (PEPCK)
E) PKA

Accepted Answer

The answer of The drug metformin is an effective treatment...

Question 19

Maturity-onset diabetes in the young (MODY) is characterized by onset prior to age 25. A defect in which of the following genes is known to result in the specific form of MODY called MODY2?&#10;A) glucose 6-phosphatase&#10;B) glucokinase&#10;C) glycogen phosphorylase&#10;D) hepatocyte nuclear factor-1a (HNF1a)&#10;E) insulin promoter factor-1 (IPF-1)

Accepted Answer

The answer of Maturity-onset diabetes in the young (MODY) is...

Question 20

Obesity is associated with hyperlipidemia resulting in an increased deliver of fatty acid to most tissues including the pancreas. Excess fatty acid oxidation in b-cells of the pancreas results in increased reactive oxygen species (ROS) production. The increased ROS production ultimately contributes to b-cell apoptosis and the need for exogenous insulin in poorly controlled Type 2 diabetes. The deleterious effects of ROS within the pancreas are amplified due to limited expression of which of the following?

A) caspase 9
B) catalase
C) glutathione peroxidase
D) peroxiredoxin
E) superoxide dismutase

Accepted Answer

The answer of Obesity is associated with hyperlipidemia resulting in...

Question 21

A 54-year-old insulin-dependent diabetic notes that her insulin requirements have gone up dramatically in the past year (from 50 U to nearly 200 U of recombinant human insulin) and her blood glucose is still poorly controlled. A possible explanation for the worsening of her diabetes includes which of the following?

A) a high titer of anti-insulin antibodies
B) an improved diet
C) an improved exercise program
D) progression of macrovascular disease
E) weight loss

Accepted Answer

The answer of A 54-year-old insulin-dependent diabetic notes that her...

Question 22

A patient with untreated diabetes mellitus is admitted to the hospital for treatment. Laboratory findings include a blood pH below 7.2. Which of the following is likely to directly result from this level of acidemia?

A) arteriolar constriction
B) decreased catabolism
C) hyperkalemia
D) hypoventilation
E) insulin sensitivity

Accepted Answer

The answer of A patient with untreated diabetes mellitus is...

Question 23

A 53-year-old man is being treated for hypertension and diabetes. His medications include insulin and propranolol. He presents at his physician's office complaining of muscle weakness. Blood tests reveal hyperkalemia (elevated serum potassium) as well as elevated BUN (blood urea nitrogen). Propranolol is gradually eliminated and his insulin dosage is adjusted. His serum potassium normalizes and his muscle weakness is alleviated. What probably caused his muscle weakness?

A) high potassium-mediated block of acetylcholine receptors
B) high potassium-mediated block of skeletal muscle calcium channels
C) motor neuron hyperpolarization
D) skeletal muscle depolarization with resultant Na-channel inactivation
E) skeletal muscle hyperpolarization with resultant Na-channel blockade

Accepted Answer

The answer of A 53-year-old man is being treated for...

Question 24

One of your diabetic patients has a blood glucose level of 200 mg/dL. Surprisingly, a dipstick test is negative for urinary glucose. How could this finding be explained?&#10;A) dipstick tests are more sensitive for reducing sugars other than glucose&#10;B) the patient has defective tubular glucose transporters&#10;C) the patient has diabetes insipidus&#10;D) the patient has significantly reduced glomerular filtration rate (GFR)&#10;E) the patient is in a state of antidiuresis

Accepted Answer

The answer of One of your diabetic patients has a...

Question 25

A 14-year-old adolescent girl presenting with polyuria is subsequently diagnosed with Type I diabetes mellitus. The polyuria results from an osmotic diuresis that involves primarily which part of the renal tubule?

A) collecting duct
B) glomerulus
C) juxtaglomerular apparatus
D) proximal tubule
E) thick ascending limb of the loop of Henle

Accepted Answer

The answer of A 14-year-old adolescent girl presenting with polyuria...

Question 26

Laboratory results for a patient with uncontrolled Type I diabetes reveal hyperglycemia (634 mg/dL) and hypertriglyceridemia (498 mg/dL). Which of the following represents the most likely cause of the hypertriglyceridemia in this patient?

A) absence of hormone-sensitive lipase
B) decreased lipoprotein lipase activity
C) deficiency in apoprotein C-II
D) deficiency in LDL receptors
E) increased hepatic triglyceride synthesis

Accepted Answer

The answer of Laboratory results for a patient with uncontrolled...

Question 27

A 48-year-old woman moved to a new area and is being seen for a routine physical examination as a new patient in a general medicine clinic. Her present medical history is significant for a 30-lb weight excess and an 8-year history of noninsulin-dependent diabetes mellitus, which she reports has been fairly well controlled with oral agents and a strict diet regimen. However, she is now anxious about her condition and admits to recently developing poor and irregular eating habits, and occasionally missing a medication dosage due to the high stress level surrounding her recent move. The most accurate estimation of this patient's recent glucose control would be which of the following?

A) fasting insulin and C-peptide levels
B) glucose tolerance test
C) glycated hemoglobin level
D) random serum glucose
E) urine ketone body level

Accepted Answer

The answer of A 48-year-old woman moved to a new...

Question 28

A 22-year-old man has come to see his physician because he feels thirsty all the time, has to urinate frequently, and is most concerned about his weight loss. Blood work demonstrates that his glucose levels are elevated and he has a slight increase in ketones. His physician makes a diagnosis of Type 1 diabetes. Which of the following additional abnormalities is most likely to be present prior to initiation of treatment?

A) decreased concentration of fructose 2,6-bisphosphate in the liver
B) decreased gluconeogenesis from alanine
C) decreased renal threshold for glucose
D) increased concentration of GLUT4 transporters in skeletal muscle
E) increased intestinal gluconeogenesis from muscle glutamine

Accepted Answer

The answer of A 22-year-old man has come to see...

Question 29

A 27-year-old woman has Type 1 diabetes. Shortly after eating lunch she measures her blood glucose with a glucose meter and finds that it is 340 mg/dL. She administers herself a dose of short-acting insulin. After this injection, which of the following is most likely to be increased in the liver of this woman?

A) cAMP
B) glucose-6-phosphatase activity
C) phosphofructokinase-1 (PFK1) activity
D) phoshorylation of pyruvate kinase
E) protein kinase A (PKA) activity

Accepted Answer

The answer of A 27-year-old woman has Type 1 diabetes....

Question 30

An unconscious 20-year-old man is brought to the ER by his frat brothers. They indicate that he had consumed several beers prior to passing out and their concern was their inability to rouse him. His best friend reports that he is Type 1 diabetic and that he injected himself with insulin about 7 hours earlier. Physical examination indicates a distinct odor of ketone on his breath. Laboratory studies demonstrate that he has an increased ketone body concentration and an increased ratio of b-hydroxybutyrate to acetoacetate in his blood. His liver cells are most likely to show which of the following ratios?

A) decreased NADH:NAD₊
B) decreased NADPH:NADP₊
C) increased NADH:NAD₊
D) increased NADPH:NADP₊
E) increased pyruvate:lactate

Accepted Answer

The answer of An unconscious 20-year-old man is brought to...

Question 31

Patients with poorly controlled Type 1 diabetes exhibit elevated plasma glucose concentration. The increases result in part because, in the absence of insulin, there is a lack of induction of glucokinase in which of the following organs?

A) brain
B) kidney
C) intestine
D) liver
E) pancreas

Accepted Answer

The answer of Patients with poorly controlled Type 1 diabetes...

Question 32

You are treating a 17-year-old adolescent girl patient with Type 1 diabetes who has not been properly and regularly injecting herself with insulin. Given your understanding of her underlying metabolic dysregulation in this disease you expect her liver to undergo an increased rate of gluconeogenesis. This metabolic process is the result of secretion of which of the following hormones?

A) aldosterone
B) glucagon
C) insulin-like growth factor-II
D) somatostatin
E) thyroid hormone

Accepted Answer

The answer of You are treating a 17-year-old adolescent girl...

Question 33

As the attending physician in the ER you are treating a 29-year-old woman brought in by her husband. He tells you that she has complained of breathing difficulty and has been nauseous and vomiting for the past 4 hours. He also reports that she has been using insulin for the past 8 years to treat her Type 1 diabetes. She indicates that she has not given herself an injection of insulin for the past 24 hours. Her pulse is 100/min, and respirations are 30/min. Physical examination indicates lethargy, dehydration, and deep respirations. Blood work show hyperglycemia and metabolic acidosis. Which of the following best describes the current activity of the metabolic pathways in this woman liver?

A) Gluconeogenesis: increased
Glycogen Synthesis: increased
Fatty Acid Oxidation: increased
Glycolysis: decreased
B) Gluconeogenesis: increased
Glycogen Synthesis: increased
Fatty Acid Oxidation: decreased
Glycolysis: decreased
C) Gluconeogenesis: increased
Glycogen Synthesis: decreased
Fatty Acid Oxidation: increased
Glycolysis: decreased
D) Gluconeogenesis: decreased
Glycogen Synthesis: increased
Fatty Acid Oxidation: increased
Glycolysis: increased
E) Gluconeogenesis: decreased
Glycogen Synthesis: decreased
Fatty Acid Oxidation: decreased
Glycolysis: decreased

Accepted Answer

The answer of As the attending physician in the ER...

Question 34

You are performing comparative tests on 2 individuals. Analysis of their blood indicates that they both have elevated levels of ketone bodies. One test subject has been on an extended fast while the other is a patient who poorly controls her Type 1 diabetes. Which of the following is a common factor that is responsible for ketosis in both of these individuals?

A) depletion of pentose phosphate pathway intermediates
B) increased availability of acetyl-CoA
C) inhibition of fatty acid oxidation
D) inhibition of gluconeogenesis
E) inhibition of glycogenolysis

Accepted Answer

The answer of You are performing comparative tests on 2...

Question 35

You are the physician treating a 14-year-old adolescent girl who has been poorly controlling her Type 1 diabetes. Blood analysis indicates that she has increased levels of hemoglobin A1c. Which of the following best explains this increase?

A) glucose competes with other sugars for glycosylation of hemoglobin
B) hemoglobin is glycosylated in erythrocyte Golgi complexes
C) hemoglobin is nonenzymatically glycosylated when serum glucose concentrations are increased
D) an increased serum glucose concentration inhibits erythrocyte degradation by spleen cells
E) an increased serum glucose concentration inhibits lysosomal degradation of hemoglobin

Accepted Answer

The answer of You are the physician treating a 14-year-old...

Question 36

You are treating a 43-year-old man with a BMI of
37) Blood tests demonstrate that he is euglycemic and has an above normal level of insulin in his blood. Which of the following best explains these findings?

A) defective glycogen synthase
B) defective glycolysis enzyme
C) low dietary intake of sugar
D) pancreatic b-cell dysfunction
E) tissue resistance to insulin

Accepted Answer

The answer of You are treating a 43-year-old man with...

Question 37

An 11-year-old boy with Type 1 diabetes is brought to the ER 1 hour after awakening from sleep at midnight in a cold sweat. He is confused and poorly responsive. He is normally given 4 injections of insulin daily, and the last injection was administered by his mother before he went to bed. Measurement of his blood glucose concentration indicates it is 37 mg/dL. Following an injection of glucagon, his serum glucose concentration increases to 145 mg/dL, and he shows clinical improvement. The beneficial effect of glucagon in this patient results from which of the following actions of this hormone in the liver?

A) adenylate cyclase stimulation
B) guanylate cyclase stimulation
C) intranuclear binding of hormone receptor to DNA
D) serine/threonine kinase activation
E) tyrosine kinase activation

Accepted Answer

The answer of An 11-year-old boy with Type 1 diabetes...

Question 38

Patients who do not maintain correct diet and exercise regimens will most often exhibit which of the following consequences of their increased serum glucose concentration?&#10;A) decreased degradation of hemoglobin A&#10;B) increased synthesis of immature erythrocytes&#10;C) insulin binding to hemoglobin A in the erythrocyte membrane&#10;D) nonenzymatic glycosylation of hemoglobin A in erythrocytes&#10;E) serum glucagon levels exceeding twice the normal levels

Accepted Answer

The answer of Patients who do not maintain correct diet...

Question 39

Type 2 diabetics retain some level of pancreatic function. This fact explains why they rarely manifest which of the following symptoms that is typical in Type 1 diabetics?&#10;A) glucose intolerance&#10;B) hyperglycemia&#10;C) ketoacidosis&#10;D) obesity&#10;E) polyuria

Accepted Answer

The answer of Type 2 diabetics retain some level of...

Question 40

You are treating a patient who recently underwent a total pancreatectomy due to pancreatic cancer. Your patient will require exogenous insulin for the same reasons as an individual with Type 1 diabetes. However, a diabetic patient will require more insulin than your pancreatectomy patient because the diabetic patient also has which of the following characteristics?

A) hyperglucagonemia in addition to insulin deficiency
B) insulin resistance
C) postreceptor defects
D) production of insulin with abnormal structure
E) receptor-mediated increases in glucagon release

Accepted Answer

The answer of You are treating a patient who recently...

Question 41

A few of the more severe complications of Type 2 of diabetes are neuropathy and retinopathy. Many of the associated pathologies of diabetes arise as a result of which of the following nonenzymatic modifications of various proteins?

A) acetylation
B) glucuronidation
C) glycosylation
D) hydroxylation
E) oxidation

Accepted Answer

The answer of A few of the more severe complications...

Deck 47: Diabetes Mellitus