HEME -L4-HEMOGLOBIN QUESTIONS AND
ANSWERS
Hemoglobin is made up of
4 globin chains (2 alpha and 2 beta, as adults) and 4 heme groups
Our haemoglobin chains are on two different chromosomes, ________.
11 (beta chains) and 16 (alpha chains)
Adult hemoglobin
2 alpha and 2 beta chains
Infant hemoglobin
predominance of gamma-globin chains
(Bind with alpha chains to form fetal haemoglobin)
Around ______ of age, we see a sharp decline in gamma chains and a
sharp increase in beta chains.
6-12 months
Adult vs. fetal hemoglobin
, If you have mutations in the _____ chain you will see the effects at birth.
alpha
If you have mutations in the _____ chain you will see the effects 6-12
months later.
beta
A thalassemia is a red blood cell disorder due to ______.
an imbalance in the normal 1:1 ratio of alpha:beta globin chain synthesis
(underproduction).
A hemoglobinopathy is a red blood cell disorder due to ______.
an abnormal hemoglobin protein, secondary to a mutation in usually the
beta globin gene
Many hemoglobin disorders evolved to protect against ______.
malaria
(Sickle cell heterozygosity protects against malarial infection)
Areas of high malaria prevalence vs areas of sickle cell anemia and
beta-thalassemia
notice they overlap
Beta thalassemia
-decreased beta globin synthesis leads to relative excess of alpha
globin, which is toxic and unstable
-ineffective erythropoiesis leads to severe transfusion-dependent anemia
-do not respond to iron
-genetic counseling needed
ANSWERS
Hemoglobin is made up of
4 globin chains (2 alpha and 2 beta, as adults) and 4 heme groups
Our haemoglobin chains are on two different chromosomes, ________.
11 (beta chains) and 16 (alpha chains)
Adult hemoglobin
2 alpha and 2 beta chains
Infant hemoglobin
predominance of gamma-globin chains
(Bind with alpha chains to form fetal haemoglobin)
Around ______ of age, we see a sharp decline in gamma chains and a
sharp increase in beta chains.
6-12 months
Adult vs. fetal hemoglobin
, If you have mutations in the _____ chain you will see the effects at birth.
alpha
If you have mutations in the _____ chain you will see the effects 6-12
months later.
beta
A thalassemia is a red blood cell disorder due to ______.
an imbalance in the normal 1:1 ratio of alpha:beta globin chain synthesis
(underproduction).
A hemoglobinopathy is a red blood cell disorder due to ______.
an abnormal hemoglobin protein, secondary to a mutation in usually the
beta globin gene
Many hemoglobin disorders evolved to protect against ______.
malaria
(Sickle cell heterozygosity protects against malarial infection)
Areas of high malaria prevalence vs areas of sickle cell anemia and
beta-thalassemia
notice they overlap
Beta thalassemia
-decreased beta globin synthesis leads to relative excess of alpha
globin, which is toxic and unstable
-ineffective erythropoiesis leads to severe transfusion-dependent anemia
-do not respond to iron
-genetic counseling needed