Hemoglobin, Hemoglobinopathies + Porphyrias Flashcards
(22 cards)
The structure of hemoglobin consists of
2 alpha & 2 beta globins, 4 heme molecules
Which aspect of the hemoglobin molecule holds onto the oxygen molecule?
Iron of the heme molecule
This hemoglobin comprises the majority of hemoglobin in adult RBCs.
Hemoglobin A
This hemoglobin is the most prevalent during fetal development.
Hemoglobin F
This hemoglobin is considered a variant and is made up of 2 alpha and 2 delta chains.
Hemoglobin A2
Functionally, how does hemoglobin A differ from hemoglobin F
Hemoglobin A has a lower affinity for oxygen
The shift in RBC production from the liver/spleen to bone marrow correlates with
A switch in production from gamma to beta globins
By 6 months, hemoglobin F is generally __ % of total hemoglobin
8%
Thalassemia is an example of a ___________hemoglobinopathy.
Quantitative
Beta thalassemia is more common in
Mediterranean
Beta thalassemia major is also known as
Cooley’s anemia
How do individuals with beta thalassemia compensate for lack of beta globin?
Increased production of hemoglobin F
Which of the following is FALSE concerning thalassemia MINOR?
It’s the most common form of thalassemia
It can be found incidentally
It presents as a severe anemia
It results in microcytic hypochromic anemia
It presents as a severe anemia
Which of the following alpha thalassemia variants results in fetal death?
1/4 alpha globin allele is deleted
2/4
3/4
4/4
4/4
Which of the following is true concerning the pathology of sickle cell disease?
Glutamic acid is substituted for valine
Alpha globins are affected
RBCs have a shorter lifespan
RBCs are conformationally changed in the deoxygenated state
Glutamic acid is substituted for valine
RBCs have a shorter lifespan
RBCs are conformationally changed in the deoxygenated state
Individuals with sickle cell disease generally make ___?%___ HgS with the remainder being hemoglobin A.
80-100%
Which of the following is NOT a theory of the Malaria Hypothesis?
Beta thalassemia may have a role in decreasing cell adhesions in a deadly form of malaria
Alpha thalassemia is associated with contracting a milder form of malaria
Hemoglobin C is associated with a more robust memory B-cell response conferring immune protection
Hemoglobin S reduces oxygen tension in cells, retarding the growth of the parasite
Hemoglobin C is associated with a more robust memory B-cell response conferring immune protection
Negative feedback from fully formed heme affects which enzyme?
ALA synthase
Heme produced in the liver is used mainly for
Synthesis of cytochrome P450 enzymes
The two cardinal symptoms in patients with porphyria are
Photosensitivity and neurological disturbance
Acute porphyria symptoms include
Abdominal pain
Seizures
Lab testing for porphyria measures ______ and ______.
It should be taken ________.
Measures build-up of porphyrins and toxic precursors
Should be taken while someone is symptomatic
