hemoglobin

Question 1

MCH

Answer 1

mean hemoglobin per cell in picograms

Question 2

most hemoglobin synthesis occurs during this stage:

Answer 2

polychromatophillic

Question 3

hb concentration

Answer 3

15 g /dL blood

Question 4

Heme synthesis

Answer 4

condensation of glycine and succinyl CoA. occurs only in presence cofactor pyridoxal phosphate and the enzyme 5-aminolevulinate synthase (ALAS). Rate limiting step only occurs in presence of iron. This step occurs in mictochondria, exits to cyoplasm to form Coproporphyrinogen then reenters mitochondria to form protoporyhyrin IX.

Question 5

ferrochelatase

Answer 5

chelates iron with protoporyphyrin Ix

Question 6

zeta chain

Answer 6

fetal alpha equivalant. very early embryonic development.

Question 7

short arm chromosome 16

Answer 7

zeta and alpha location. two alpha loci.

Question 8

Beta like genes

Answer 8

located in order of activation on chromosome 11. E, Gamma, D and B.

Question 9

non alpha affinity for alpha

Answer 9

Beta > gamma > delta

Question 10

AHSP alpha hemoglobin stabilizing protein

Answer 10

AHSP binds free a@chains and stabilizes their structure, increasing their affinity for b@chains. This accelerates the formation of hemoglobin tetramers.

McKenzie, Shirlyn B.; Williams, Lynne. Clinical Laboratory Hematology (3rd Edition) (Pearson Clinical Laboratory Science Series) (Page 82). Prentice Hall. Kindle Edition.

Question 11

Heme binding position

Answer 11

6 electrons in iron. four bind heme, 1 binds proimal histidine F8 other is for oxygen. Located between proximal and distal E8 histidine.

Question 12

Regulation of hemoglobin synthesis

Answer 12

activity concnetration of ALAS2,

Activity of porphobilinogen deaminase (PBGD) • Concentration of iron • Regulation of globin chain synthesis

Question 13

Heme role in regulation

Answer 13

inhibits mitochondrial import of ALAS 2, inhibits iron uptake via transferrin. Decreased iron inhibits ALAS2 synthesis.