MIDTERM RODAKS Flashcards
a tetramer composed of two pairs of unlike polypeptide chains
hemoglobin molecule
heme group
protoporphyrin IX 1 Fe2+
bound to each of the four polypeptide chains
heme group
carries oxygen from the lungs to the tissues
Hemoglobin, contained in RBCs
Oxygen binds to the
ferrous iron in heme
Each hemoglobin tetramer can bind [?] oxygen molecules
four
Six structural genes code for the
Six globin chains of hemoglobin
genes are on chromosome 16
Alpha and zeta
genes are on chromosome 11
Epsilon lambda delta beta
There is one copy of which globin genes per chromosome, for a total of two genes per diploid cell
1 delta
1 beta
There are two copies of which globin genes per chromosome, for a total of four genes per diploid cell
Alpha and lambda
The three hemoglobins found in normal adults are
Hb A, Hb A2, and Hb F
composed of two ab heterodimers, is the pre ominant hemoglobin of adults
Hb A (a2b2)
is the predominant hemoglobin in the fetus and newborn
Hb F (a2g2)
is present from birth through adulthood, but at low levels
Hb A2 (a2d2)
describes which hemoglobins are produced by the erythroid precursor cells from the fetal period through birth to adulthood
Hemoglobin ontogeny
Complex genetic mechanisms regulate the sequential expression
of the polypeptide chains in the
embryo, fetus, and adult
Heme provides negative feedback regulation on
protoporphyrin and globin chain production
owing to cooperativity among the hemoglobin subunits in binding and re easing oxygen
sigmoid
facilitates the delivery of oxygen from hemoglobin to the tissues
2,3-BPG
the influence of pH on the release of oxygen from hemoglobin
Bohr effect
[?] diffuses into the [?] and combines with [?] to form [?]
carbon dioxide
RBCs
water
carbonic acid
The carbonic acid is then converted to
bicarbonate and hydrogen ions
Most of the carbon dioxide is carried by hemoglobin as
H+
