BLD 402 - EXAM 2 QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED GRADED A++
Bilirubin trafficking:
Heme → ________________ → unconjugated bilirubin → conjugated bilirubin →
__________________
biliverdin; urobilinogens
In the breakdown of hemoglobin, macrophages and heme oxygenase...
separate heme and globin, convert Fe2+ to Fe3+.
After heme and globin have been separated, heme oxygenase...
converts heme to biliverdin.
(CO is exhaled, Fe is recycled)
Unconjugated bilirubin binds to albumin because its ___________________ in
water.
insoluble
Hepatic uptake of bilirubin
Unconjugated bilirubin binds to transport protein to cross the hepatic cell membrane,
and leaves albumin.
Unconjugated bilirubin binds to ligandin because it is insoluble in water.
Conjugation of bilirubin
,UDP-glucuronyl transferase adds one or two glucuronyl groups (very polar) →
conjugation (now water soluble).
Conjugated bilirubin is excreted to bile ________________--> becomes
component of ________.
canaliculus; bile
_________________________ _______________ convert conjugated bilirubin to
urobilinogens.
Intestinal flora
Some of urobilinogens are reabsorbed at the _________(end of intestine) →
_________ vein → either re-excreted to bile or excreted from kidney.
ileum; portal
Intestinal flora convert urobilinogens to urobilins, and then to
________________________
stercobilins
Hyperbilirubinemia causing yellow discoloration of skin and mucous membranes.
Jaundice
Overproduction of conjugated bilirubin, lab results are increased indirect
bilirubin, increased urobilinogen, and no bilirubin in urine
Prehepatic Jaundice
Viral, drug or toxin induced. Increased direct bilirubin, increased indirect
bilirubin, bilirubin present in urine, and increased urine urobilinogen
Hepatic Jaundice (Hepatitis)
,Synthesis of UDP-glucuronyl transferase starts a few days after birth. Jaundice
starts when albumin is saturated with unconjugated bilirubin. Treated with blue
light.
Neonatal Jaundice
Hereditary UDP-glucuronyl transferase defect. Indirect bilirubin. Type 1: complete
absence of enzyme activity leads to needing a liver transplant. Type 2: reduced
enzyme activity leads to milder symptom
Crigler-Najjar Syndrome
Reduced UDP-glucuronyl transferase activity by mutation. Mildly increased
indirect bilirubin, no treatment needed.
Gilbert's Disease
Autosomal recessive disorder causing defect in canalicular secretion of
conjugated bilirubin. Increased direct bilirubin, usually benign
Dubin-Johnson syndrome
Caused by any obstruction of bile flow. Cause by gallstones, tumor, parasite
enters from duodenum. Increased direct bilirubin, low/no urobilinogen in serum
and urine, less/no brown color to stool
Posthepatic jaundice
-Synthesis of most plasma proteins (except Igs).
-Metabolisms/storage of carbs, protein, lipids, porphyrins, vitamins.
-Detoxification.
, -Excretion of wastes: bilirubin, urea, cholesterol, etc.
Normal Functions of the liver.
Consequences of decreased total serum protein:
-Decreased functional protein (coag factors, complements, enzymes).
-Decreased Colloid Osmotic (oncotic) pressure (can't hold water in blood, causing
edema).
Total serum protein does not decrease until the number of functioning liver cells
____________________ a lot.
decreases
Causes of Decreased Total Serum Protein
-Liver function - amino acid intake (starvation, digestion/absorption),
-hydration (blood dilution)
-Loss of protein (decreased glomerular integrity).
Causes of Increased Total Serum Protein
-Acute phase protein (increased),
-immunoglobulin (increased),
-Abnormal protein Increases (multiple myeloma, etc.),
COMPLETE SOLUTIONS VERIFIED GRADED A++
Bilirubin trafficking:
Heme → ________________ → unconjugated bilirubin → conjugated bilirubin →
__________________
biliverdin; urobilinogens
In the breakdown of hemoglobin, macrophages and heme oxygenase...
separate heme and globin, convert Fe2+ to Fe3+.
After heme and globin have been separated, heme oxygenase...
converts heme to biliverdin.
(CO is exhaled, Fe is recycled)
Unconjugated bilirubin binds to albumin because its ___________________ in
water.
insoluble
Hepatic uptake of bilirubin
Unconjugated bilirubin binds to transport protein to cross the hepatic cell membrane,
and leaves albumin.
Unconjugated bilirubin binds to ligandin because it is insoluble in water.
Conjugation of bilirubin
,UDP-glucuronyl transferase adds one or two glucuronyl groups (very polar) →
conjugation (now water soluble).
Conjugated bilirubin is excreted to bile ________________--> becomes
component of ________.
canaliculus; bile
_________________________ _______________ convert conjugated bilirubin to
urobilinogens.
Intestinal flora
Some of urobilinogens are reabsorbed at the _________(end of intestine) →
_________ vein → either re-excreted to bile or excreted from kidney.
ileum; portal
Intestinal flora convert urobilinogens to urobilins, and then to
________________________
stercobilins
Hyperbilirubinemia causing yellow discoloration of skin and mucous membranes.
Jaundice
Overproduction of conjugated bilirubin, lab results are increased indirect
bilirubin, increased urobilinogen, and no bilirubin in urine
Prehepatic Jaundice
Viral, drug or toxin induced. Increased direct bilirubin, increased indirect
bilirubin, bilirubin present in urine, and increased urine urobilinogen
Hepatic Jaundice (Hepatitis)
,Synthesis of UDP-glucuronyl transferase starts a few days after birth. Jaundice
starts when albumin is saturated with unconjugated bilirubin. Treated with blue
light.
Neonatal Jaundice
Hereditary UDP-glucuronyl transferase defect. Indirect bilirubin. Type 1: complete
absence of enzyme activity leads to needing a liver transplant. Type 2: reduced
enzyme activity leads to milder symptom
Crigler-Najjar Syndrome
Reduced UDP-glucuronyl transferase activity by mutation. Mildly increased
indirect bilirubin, no treatment needed.
Gilbert's Disease
Autosomal recessive disorder causing defect in canalicular secretion of
conjugated bilirubin. Increased direct bilirubin, usually benign
Dubin-Johnson syndrome
Caused by any obstruction of bile flow. Cause by gallstones, tumor, parasite
enters from duodenum. Increased direct bilirubin, low/no urobilinogen in serum
and urine, less/no brown color to stool
Posthepatic jaundice
-Synthesis of most plasma proteins (except Igs).
-Metabolisms/storage of carbs, protein, lipids, porphyrins, vitamins.
-Detoxification.
, -Excretion of wastes: bilirubin, urea, cholesterol, etc.
Normal Functions of the liver.
Consequences of decreased total serum protein:
-Decreased functional protein (coag factors, complements, enzymes).
-Decreased Colloid Osmotic (oncotic) pressure (can't hold water in blood, causing
edema).
Total serum protein does not decrease until the number of functioning liver cells
____________________ a lot.
decreases
Causes of Decreased Total Serum Protein
-Liver function - amino acid intake (starvation, digestion/absorption),
-hydration (blood dilution)
-Loss of protein (decreased glomerular integrity).
Causes of Increased Total Serum Protein
-Acute phase protein (increased),
-immunoglobulin (increased),
-Abnormal protein Increases (multiple myeloma, etc.),
