Clin Chem II Exam 2

The major risk factor for development of hepatocellular carcinoma is:
Hepatorenal syndrome
Infection with hepatitis B or C viruses
Hepatic encephalopathy
Infection with hepatitis A virus

Infection with hepatitis B or C viruses

The functional unit of the liver is the:
Cord
Glomerulus
Nephron
Acinus

Acinus

Bilirubin that is attached to albumin before it is transported across the hepatocyte membrane is called:
Urobilinogen
Conjugated bilirubin
Unconjugated bilirubin
Jaundice

Unconjugated bilirubin

The first protein marker to appear approximately 1 to 2 months after infection with the hepatitis B virus and also the last marker to disappear is the:
Hepatitis B surface antigen
Antihepatitis B core antigen
Hepatitis B immune globulin
Antihepatitis B surface antigen

Hepatitis B surface antigen

Which one of the following is not a consequence of portal hypertension in an individual?
Hemochromatosis
Bleeding esophageal varices
Increased prothrombin time
Altered estrogen metabolism

Hemochromatosis

A Model for End-Stage Liver disease staging system to predict prognosis in cirrhosis uses the following laboratory determinations EXCEPT:
INR
Bilirubin
Creatinine
Aspartate transaminase

Aspartate transaminase

Nonalcoholic steatohepatitis is characterized by all of the following EXCEPT:
AST greater than ALT
Consumption of less than 20g of ethanol daily
Necroinflammatory liver disease associated with accumulation of fat in the liver
No inflammation or scarring of the liver

AST greater than ALT

The liver is supplied by what major source(s) of oxygen-containing blood?
Portal vein
Hepatic artery
Hepatic vein
Both A and B

Both A and B

Which type of hepatitis is a leading cause of chronic hepatitis and is caused by a mutating RNA virus?
Hepatitis A
Hepatitis C
Hepatitis B
Fulminant hepatitis

Hepatitis C

Deficiency of which of the following vitamins will result in decreased heme synthesis?
Niacin
Pyridoxal phosphate (PLP)
Thiamine
Riboflavin

Pyridoxal phosphate (PLP)

Which one of the following vitamins will aid in the absorption of iron by the intestine?
C
B12
A
D

C

The most commonly used method of analysis for assessing vitamins A, K, and B6 is:
Immunoassay
High performance liquid chromatography (HPLC)
Competitive protein binding
Spectrophotometry

High performance liquid chromatography (HPLC)

Production of bilirubin occurs in the ______, and conjugation of bilirubin to glucuronide occurs in the ______
RES, liver
RES, intestine
Liver, RES
Liver, Intestine

RES; liver

Serum bilirubin is unstable because of:
Precipitates on standing
Digestion by proteolytic enzymes
Light sensitivity
Precipitation due to acid pH

Light sensitivity

The enzyme that conjugates bilirubin in the hepatocyte is:
Glucuronic aminotransferase
Biliverdin reductase
UDP-glucuronyl transferase
Microsomal heme oxygenase
Beta-glucuronidase

UDP-glucuronyl transferase

What reagent is used in the bilirubin method to shift the color reaction to a wavelength with less interference?
Ascorbic acid
Active diazo
Alkaline tartrate
Hydrochloric acid

Alkaline tartrate

Acute intermittent porphyria (AIP) patients have a deficiency of:
Protoporphyrinogen oxidase
Coproporphyrinogen oxidase
PBG deaminase
Ferrochelatase

PBG deaminase

The number of pyrrole rings found in the structure of all porphyrins is:
4
3
2
8

4

Bile formed in the liver is stored in the:
Gall bladder
Duodenum
Large intestine
Liver

Gall bladder

A breakdown product of bilirubin metabolism that is produced in the colon from the oxidation of urobilinogen by microorganisms is:
Protoheme
Porphobilinogen
Urobilin
Protoporphyrin
Stercobilinogen

Urobilin

Which of the statements regarding bilirubin metabolism is TRUE?
It is a product of porphyrin metabolism
It is reduced to biliverdin before excretion
It is formed by the hydrolysis of the α-methene bridge of urobilingen
It is produced from the destruction of RBCs

It is produced from the destruction of RBCs

Which is a characteristic of unconjugated bilirubin?
It is water-soluble
It has the same absorbance properties as conjugated bilirubin
It reacts faster than conjugated bilirubin
It a not water-soluble.

It a not water-soluble.

The term δ-bilirubin (delta) refers to:
Direct-reacting bilirubin
Bilirubin tightly bound to albumin
Water-soluble bilirubin
Free unconjugated bilirubin.

Bilirubin tightly bound to albumin

What is the most common cause of unconjugated hyperbilirubinemia?
Hemolytic anemia
Gilbert's disease
Dubin-Johnson
Bile duct obstruction
Neonatal physiologic jaundice

Neonatal physiologic jaundice

In obstructive liver disease, the following test results are found:
Feces: urobilinogen decreased; urine: bilirubin: positive; serum: conjugated bilirubin increased.
Feces: urobilinogen decreased or negative; urine: urobilinogen decreased or negative; serum: conjugated bilirubin decreased.
Feces: urobilinogen increased; urine: bilirubin: normal; serum: conjugated bilirubin normal or slightly elevated.
None of the above.

Feces: urobilinogen decreased; urine bilirubin: positive; serum conjugated bilirubin: increased.

Alcoholic liver disease that follows six months to a year of moderate consumption, few lab abnormalities, and is reversible with abstinence from alcohol is termed:
Alcoholic hepatitis
Alcoholic cirrhosis
Alcoholic fatty liver
None of the above

Alcoholic fatty liver

The reagent (accelerator) in the Jendrassik-Grof bilirubin procedure that makes indirect bilirubin water-soluble is:
Hydrochloric acid
Methanol
Caffeine
Alkaline tartrate

Caffeine

If a total bilirubin is 4.0 mg/dL and the conjugated bilirubin is 2.5 mg/dL, the unconjugated bilirubin is:
1.5 mg/dL
2.0 mg/dL
1.0 mg/dL
3.0 mg/dL

1.5 mg/dL

In the Jendrassik-Grof bilirubin, what converts purple azobilirubin to blue azobilirubin measured at 600nm?
Alkaline tartrate
Methanol
Hydrochloric acid
Caffeine

Alkaline tartrate

Viral hepatitis that results in the largest percentage of chronic hepatitis is:
Hepatitis A
Hepatitis B
Hepatitis C
Hepatitis D

Hepatitis C

The type of RNA virus that is considered to be the cause of the most common type of acute hepatitis that does not lead to chronic hepatitis is:
Reye syndrome
Hepatitis C
Hepatitis A
Hepatitis B

Hepatitis A

In the liver, ammonia is metabolized to form:
Ketoacids
Amino acids
Urea
Glucuronic acid

Urea

Caffeine is used in bilirubin assays to:
Reduce sodium nitrite
Accelerate indirect bilirubin reaction
Stop the diazo reaction
Precipitate proteins
Accelerate direct bilirubin reaction

Accelerate indirect bilirubin reaction

When elevated amounts of bilirubin are presented to the liver with elevated serum unconjugated bilirubin, what type of jaundice occurs?
Biliary
Hepatic
Posthepatic
Prehepatic

Prehepatic

The placenta secretes numerous hormones, both protein and steroid. Which of the following hormones is not secreted by the placenta?
Progesterone
Human chorionic gonadotropin (HCG)
Estrogen
Human placental lactogen (HPL)
Luteinizing hormone (LH)

Luteinizing hormone (LH)

The FINAL metabolite of epinephrine that is measured in urine is:
Metanephrines
Dopamine
Homovanillic acid
Vanillylmandelic acid

Vanillylmandelic acid

The test for adrenal cortical hyperfunction that has the greatest diagnostic sensitivity is measurement of:
Urinary free cortisol
Urinary 17-hydroxycorticosteroids
Plasma corticosterone
Plasma cortisol

Urinary free cortisol

As a screening test for Cushing's syndrome, the physician wishes to see whether a patient exhibits normal diurnal rhythm of his cortisol secretion. At what time should the specimens be drawn for plasma cortisol determination? (Assume a daytime work schedule for the patient.)
8 AM, 8 PM
8 AM, 2 PM
Noon, 6 PM
Noon, midnight
6 AM, noon

8 AM, 8 PM

In a patient who is suspected of having pheochromocytoma, measurement of which of the following urinary compounds would be the most useful?
Dopamine
Vanillylmandelic acid
Catecholamines
Homovanillic acid
Metanephrines

Metanephrines

Measurement of urinary metanephrine and vanillylmandelic acid (VMA) assesses the amount of hormone secreted by the _____ and is done to detect the presence of ________
adrenal cortex; Cushing syndrome
medulla of the brain; neuroblastoma
gastrointestinal (GI) tract; carcinoid tumor
adrenal medulla; pheochromocytoma

adrenal medulla; pheochromocytoma

Which one of the following substances is measured in urine to determine the presence of a gastroenteropancreatic neuroendocrine tumor in an individual with carcinoid syndrome?
VMA
Homovanillic acid (HVA)
5-Hydroxyindole acetic acid (5-HIAA)
Metanephrine

5-Hydroxyindole acetic acid (5-HIAA)

In the assessment of equivocal results in pheochromocytoma testing, the clonidine suppression test is used to differentiate between:
elevated blood pressure caused by pheochromocytoma versus that caused by carcinoid tumor.
adrenal gland and GI tract increased synthesis of dopamine.
adrenal gland and sympathetic nervous system increases in catecholamine synthesis.
increased serotonin production by the GI tract versus serotonin from the brain.

adrenal gland and sympathetic nervous system increases in catecholamine synthesis.

Pheochromocytomas:
are tumors derived from enterochromaffin cells.
are benign in the majority of cases.
produce hypotension (decreased blood pressure).
tend to secrete serotonin in increased amounts.

are benign in the majority of cases.

The amino acid precursor for the neurotransmitter serotonin (5HT) is:
tyrosine.
threonine.
tryptophan.
cytosine.

tryptophan.

Metabolism of norepinephrine and epinephrine in adrenal chromaffin cells requires the presence of which one of the following enzymes for conversion into normetanephrine and metanephrine?
Monoamine oxidase
Tyrosine hydroxylase
Dopamine-beta-hydroxylase
Catechol-O-methyltransferase

Catechol-O-methyltransferase

An overnight fast is recommended for individuals being tested for carcinoid syndrome because:
certain foods interfere with the methods of analysis used for serotonin analysis, particularly the high performance liquid chromatography (HPLC) assays.
dietary interference, particularly with foods that contain 5-hydroxyindoles, will produce a false increase in plasma 5-HIAA measurement.
no food should be present in the GI tract for 12 hours before analysis of catecholamine metabolites.
monoamine systems are targets of certain components of foods that contain tyrosine, and a false-negative result will occur in HVA testing.

dietary interference, particularly with foods that contain 5-hydroxyindoles, will produce a false increase in plasma 5-HIAA measurement.

The urinary metabolite measured as an indicator of dopamine synthesis is:
homovanillic acid.
vanillylmandelic acid.
metanephrine.
catechol-O-methyltransferase.

homovanillic acid.

The rate-limiting step in the biosynthesis of catecholamines is the:
metabolism by catechol-O-methyltransferase (COMT) to MHPG.
conversion of 3-methoxy-4-hydroxyphenylglycol (MHPG) to VMA by alcohol dehydrogenase.
conversion of tyrosine to 3,4-dihydroxyphenylalanine by tyrosine hydroxylase.
conversion of tryptophan to 5-hydroxytryptophan by tryptophan hydroxylase.

conversion of tyrosine to 3,4-dihydroxyphenylalanine by tyrosine hydroxylase

Currently, the most common method of analysis for plasma catecholamines is:
HPLC.
liquid chromatography (LC) with electrochemical (EC) detection.
spectrophotometry.
mass spectrometry.

liquid chromatography (LC) with electrochemical (EC) detection.

All of the following represent metabolic effects caused by the action of epinephrine secreted from the adrenal gland except:
glycogenolysis.
bronchodilation.
increased protein synthesis.
increased lipolysis.

increased protein synthesis.

The follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are important in the reproductive function of the male and female and are released in response to:
gonadotropin-releasing hormone (GnRH).
TSH.
oxytocin.
corticotrophin-releasing hormone (CRH).

gonadotropin-releasing hormone (GnRH).

Which one of the following hormones is classified as a glycoprotein?
Follicle-stimulating hormone
Growth hormone
Adrenocorticotropic hormone
Prolactin

Follicle-stimulating hormone

Androgen secretion by the testes is stimulated by:
Testosterone
Gonadotropins
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)

Luteinizing hormone (LH)

A genetic disorder causing a deficiency of certain enzymes in the synthetic pathways leading to cortisol and aldosterone production is referred to as:
Congenital adrenal hyperplasia
Conn's syndrome
Addison's disease
Cushing's syndrome

Congenital adrenal hyperplasia

The anterior portion of the pituitary gland synthesizes many protein hormones. Another name for this part of the pituitary gland is the:
neurohypophysis.
hypothalamus.
hypophysis.
adenohypophysis.

adenohypophysis.

The hypothalamic hormone that inhibits prolactin is referred to as prolactin-inhibiting hormone but is actually:
adrenaline.
interleukin 1.
dopamine.
thyrotropin.

dopamine.

Which one of the following hormones causes the hypothalamus to trigger the surge of luteinizing hormone (LH) from the anterior pituitary just before ovulation?
Gonadotropin-releasing hormone (GnRH)
Follicle-stimulating hormone (FSH)
Estrogen
Progesterone

Estrogen

What would the laboratory results be in a male patient exhibiting characteristic symptoms of hypogonadotropic hypogonadism?
Elevated testosterone, elevated FSH
Decreased testosterone, decreased FSH
Decreased testosterone, elevated FSH
Elevated testosterone, decreased FSH

Decreased testosterone, decreased FSH

During the luteal phase, which hormone, when decreased in the absence of conception, releases its inhibition on pituitary gland synthesis and release of FSH?
Chorionic gonadotropin
Estrone
Progesterone
Estradiol

Estradiol

Which one of the following hormones shuts off synthesis and release of LH from the male pituitary gland?
FSH
Testosterone
Prolactin
Inhibin

Testosterone

Inhibin:
inhibits release of FSH from the male pituitary gland.
increases in males with elevated GnRH.
augments release of LH from the male pituitary gland.
promotes synthesis of testosterone by the Sertoli cells.

inhibits release of FSH from the male pituitary gland.

For the past 3 weeks, serum estriol levels in a pregnant woman have been steadily increasing. This is consistent with:
Hemolytic disease of the newborn
A normal pregnancy
Fetal death
Congenital cytomegalovirus infection

A normal pregnancy

Which of the following is secreted by the placenta and used for the early detection of pregnancy?
Luteinizing hormone (LH)
Human chorionic gonadotropin (HCG)
Progesterone
Follicle-stimulating hormone (FSH)

Human chorionic gonadotropin (HCG)

In nonpregnant women, progesterone is synthesized and secreted by the:
pituitary gland.
placenta.
corpus luteum.
both a and b are correct

corpus luteum

Typical findings in a woman in menopause include:
decreased estrogen and inhibin.
increased progesterone.
decreased serum LH/FSH.
hirsutism.

decreased estrogen and inhibin.

Which one of the following statements regarding FSH/LH is incorrect?
FSH acts on the cells of the follicle to increase responsiveness of LH receptors.
FSH, secreted by the anterior pituitary, induces follicular maturation.
Progesterone produced by the corpus luteum causes LH levels to increase.
LH acts to stimulate Leydig cells in the testes to synthesize testosterone.

Progesterone produced by the corpus luteum causes LH levels to increase.

Early activation of the hypothalamic-pituitary-gonadal axis in a young child will lead to:
GnRH-dependent precocious puberty.
pseudoprecocious puberty.
pseudohermaphroditism.
GnRH-independent precocious puberty.

GnRH-dependent precocious puberty.

In measurement of testosterone in blood:
5-androstenediol derivatives are actually measured.
specimens must be collected in EDTA anticoagulant.
assessment of serum 17-ketosteroids is included.
morning specimens are preferred because of the diurnal release of testosterone.

morning specimens are preferred because of the diurnal release of testosterone.

Dehydroepiandrosterone sulfate (DHEA-S):
is an important screening test used to evaluate women with hirsutism and virilization.
concentration is increased in 17-hydroxylase deficiency-caused amenorrhea.
concentrations exhibit a circadian rhythm that reflects the secretion of adrenocorticotropic hormone (ACTH).
analysis is performed using heparinized plasma.

is an important screening test used to evaluate women with hirsutism and virilization.

The analytical method that provides better analytical sensitivity in hormone detection than other methods such as immunoassay or receptor-based assays is:
spectrophotometry.
immunometric assay.
bioassay.
tandem mass spectrometry.

tandem mass spectrometry.

A man visits his physician complaining of hypertension (elevated heart rate and blood pressure), periodic bouts of profuse sweating, and occasional severe headaches. These symptoms are indicative of:
pheochromocytoma.
neuroblastoma.
carcinoid syndrome.
Cushing syndrome.

pheochromocytoma.

Which one of the following statements concerning steroid hormones is correct?
Steroid hormones, because of their structure, are not bound to carrier proteins as they circulate in the As a screening test for Cushing's syndrome blood.
Steroid hormones attach to a receptor on the surface of a cell, which eventually induces enzyme phosphorylation within the cell.
Steroid hormones have a very short half-life (usually

Steroid hormones are hydrophobic when free and bind to intracellular receptors in the nucleus.

Which one of the following hormones causes the hypothalamus to trigger the surge of luteinizing hormone (LH) from the anterior pituitary just before ovulation?
Gonadotropin-releasing hormone (GnRH)
Follicle-stimulating hormone (FSH)
Estrogen
Progesterone

Estrogen

Because of the biochemical properties of steroid hormones, the majority of these hormones, at physiological concentration:
remain free in the circulation.
are bound with high affinity to a carrier protein in the circulation.
are conjugated to glucuronides.
are bound with low affinity to albumin.

are bound with high affinity to a carrier protein in the circulation

The urinary metabolite of cortisol and adrenal androgens is:
17-ketosteroid.
17-hydroxyprogesterone.
renin.
11-desoxycortisol.

17-ketosteroid

In the classic plasma renin activity assay that measures the main function of the enzyme and uses inhibitors of angiotensinase, what is actually measured at the end of the assay?
Plasma renin
Angiotensin I
Angiotensin II
Angiotensin-converting enzyme

Angiotensin I

Laboratory assessment of which of the following hormones is used to evaluate ovulation?
All of the above
Estradiol
Progesterone
FSH

Progesterone

Which one of the following statements concerning androstenedione is incorrect?
Androstenedione metabolites are measured as 17-ketosteroids.
11-Hydroxylase deficiency leads to elevated plasma androstenedione.
The precursor molecule in the formation of androstenedione is dihydroepiandrostenedione (DHEA).
In adrenal carcinoma, cortisol is greatly elevated, but androstenedione is greatly decreased.

In adrenal carcinoma, cortisol is greatly elevated, but androstenedione is greatly decreased.

A typical characteristic in a woman with polycystic ovary disease (PCOS) includes:
increased serum LH concentration.
decreased serum androstenedione concentration.
markedly increased serum FSH concentration.
persistent ovulation.

increased serum LH concentration.

In nonpregnant women, progesterone is synthesized and secreted by the:
pituitary gland.
corpus luteum.
placenta.
Both a and b are correct.

corpus luteum.

Typical findings in a woman in menopause include:
decreased serum LH/FSH.
hirsutism.
increased progesterone.
decreased estrogen and inhibin.

decreased estrogen and inhibin.

Which one of the following statements regarding FSH/LH is incorrect?
LH acts to stimulate Leydig cells in the testes to synthesize testosterone.
FSH acts on the cells of the follicle to increase responsiveness of LH receptors.
FSH, secreted by the anterior pituitary, induces follicular maturation.
Progesterone produced by the corpus luteum causes LH levels to increase.

Progesterone produced by the corpus luteum causes LH levels to increase.

Renin is synthesized in the …………….. and stimulates the production of angiotensin I, which eventually leads to ……………
adrenal gland; an increase in blood pressure and volume
kidney; lowering of the blood pressure and volume
adrenal gland; stimulation of cortisol production
kidney; stimulation of aldosterone production

kidney; stimulation of aldosterone production

Deficiency of which of the following enzymes can lead to congenital adrenal hyperplasia (CAH)?
17-Ketosteroidase
21-Alpha-hydroxylase
11-Beta-hydroxylase
Both a and b

17-Ketosteroidase

In measurement of testosterone in blood:
assessment of serum 17-ketosteroids is included.
specimens must be collected in EDTA anticoagulant.
5-androstenediol derivatives are actually measured.
morning specimens are preferred because of the diurnal release of testosterone.

morning specimens are preferred because of the diurnal release of testosterone.

How would CAH affect cortisol and adrenal androgen levels in blood?
Cortisol decreased, adrenal androgens decreased
Cortisol increased, adrenal androgens increased
Cortisol increased, adrenal androgens decreased
Cortisol decreased, adrenal androgens increased

Cortisol decreased, adrenal androgens increased

Inhibin:
inhibits release of FSH from the male pituitary gland.
increases in males with elevated GnRH.
augments release of LH from the male pituitary gland.
promotes synthesis of testosterone by the Sertoli cells.

inhibits release of FSH from the male pituitary gland.

A 14-year-old male comes to his physician with infantile genitalia and the lack of development of any secondary sex characteristics. The patient is short in stature. Upon discussion of family history, it was discovered that several male relatives had similar defects in testicular development. Based on this information, laboratory results would indicate:
decreased testosterone and elevated FSH/LH.
elevated testosterone and elevated FSH/LH.
decreased testosterone and decreased follicle-stimulating hormone (FSH)/luteinizing hormone (LH).
elevated testosterone and decreased FSH/LH.

decreased testosterone and elevated FSH/LH.

Glucocorticoids:
stimulate lipogenesis.
stimulate erythropoiesis.
repress inflammatory genes.
decrease blood glucose concentration.

repress inflammatory genes.

A patient with Cushing syndrome has plasma cortisol measured at 8 AM. The nighttime cortisol level will be ………. from the 8 AM value.
increased
decreased
unchanged

unchanged

Regarding the phases of the menstrual cycle, the suppression of luteinizing hormone synthesis by progesterone occurs during which one of the following phases?
Luteal phase
Follicular phase
Ovulation
Both a and b

Luteal phase

The parent substance in the biosynthesis of androgens and estrogens is:
Progesterone
Cortisol
Cholesterol
Catecholamines

Cholesterol

The adrenal cortical hormone that promotes sodium resorption and potassium and hydrogen ion excretion by the renal tubules and thus affects water balance in the body is:
androstenedione.
cortisol.
aldosterone.
calcium.

aldosterone

The formation of estriol in a pregnant woman is dependent on:
Fetal adrenal function
Maternal ovarian function
Fetal and placental function
Maternal liver function

Fetal and placental function

For the past 3 weeks, serum estriol levels in a pregnant woman have been steadily increasing. This is consistent with:
A normal pregnancy
Congenital cytomegalovirus infection
Fetal death
Hemolytic disease of the newborn

A normal pregnancy

Which of the following is secreted by the placenta and used for the early detection of pregnancy?
Human chorionic gonadotropin (HCG)
Follicle-stimulating hormone (FSH)
Progesterone
Luteinizing hormone (LH)

Human chorionic gonadotropin (HCG)

Which of the following steroid hormones is (are) synthesized and secreted by the zona reticularis of the adrenal cortex?
Androstenedione
Estradiol
Cortisol
All of the above

Androstenedione

The primary glucocorticoid is:
glucose.
epinephrine.
aldosterone.
cortisol.

cortisol

During an evaluation of adrenal function, a patient had plasma cortisol determinations in the morning after awakening and in the evening at approximately 7:30 PM. Laboratory results indicated that the evening value was approximately half as high as the morning concentration. This is indicative of:
A normal finding.
Adrenal gland tumor.
Cushing syndrome.
Ectopic hormone production

A normal finding

The most potent estrogen, and the substance considered to be the true ovarian hormone, is:
Estrone
Estriol
Estradiol
Epiestriol

Estradiol