1.31: Iron, Bilirubin, Porphyrin
- Page ID
- 38611
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FOR QUESTIONS 1 - 3 use the following KEY:
- formation of amino levulinic acid (ALA) by ALA synthase
- conversion of ALA to porphobilinogen (PB) by ALA dehydratase
- conversion of PB to Uroporphyrin I
- conversion of PB to Uroporphyrin III
- conversion of coproporphyrin to protoporphyrinogen IX
- Normally the feed—back inhibition by Heme operates at which one of the above steps?:
- In acute intermittent porphyria this rate-limiting step is defective:
- This step is severely inhibited by lead:
Use the following Key to answer Questions 4-9:
- 1, 2, and 3 are correct
- 1 and 3 are correct
- 2 and 4 are correct
- only 4 is correct
- all are correct
- Most of the iron in the body is found in:
- hemoglobin
- haptoglobin
- ferritin
- peroxides
- The transport protein(s) of iron is/are:
- ferritin
- haptoglobin
- hemosiderin
- transferrin
- The total iron binding capacity (TIBC) calculated from:
- transferrin
- ferritin
- serum iron
- hemosiderin
- Heme is degraded to form the following compounds:
- a linear tetraphrrole
- biliverdin
- bilirubin
- protoporphyrin
- Bilirubin is bound by which of the following compound(s)?
- bile acids
- haptoglobin
- hemoglobin
- albumin
- Heme synthesis is an integral part of which of the following body systems?
- respiratory
- bone marrow
- genitourinary
- hepatic
- Delta bilirubin is:
- free, unconjugated bilirubin
- unconjugated bilirubin, covalently bound to albumin
- bilirubin monoglucuronide
- conjugated bilirubin that does not react in direct reaction
- none of the above
- Measurement of urinary urobilinogen is:
- useful in detection of renal disease
- useful in detection of inborn errors of heme synthesis
- useful in detection of liver disease
- useful for screening for porphobilinogens
- not particularly useful for any of the above
- Answer
-
- a (p. 664)
- d (p. 665-667)
- b (p. 669)
- b (p. 659)
- d (p. 660)
- b (p. 661-662)
- a (p. 671)
- d (p. 671)
- c (p. 664)
- b (p. 671)
- e (p. 673)