Oxygen Transport- Lecture 8/27/21

Question 1

Myoglobin

Answer 1

Has one heme group, found in muscle, releases O2 at very low ppO2

Question 2

Oxygenation

Answer 2

When an O2 binds to Fe2+ in the heme group

Question 3

Oxidation

Answer 3

When the iron is oxidized, causing a Fe3+

Question 4

Proxima histidine

Answer 4

Forms a ligand to the iron that moves on oxygenation

Question 5

Hemoglobin

Answer 5

HbA has two subunits, 2 alpha and 2 beta all containing a heme group

Question 6

Hill coefficient

Answer 6

No cooperatively has a hill coefficient of 1 and positive is more than one

Question 7

T state

Answer 7

Tense state binds the oxygen less easily, favored in low oxygen conditions

Question 8

R state

Answer 8

relaxed state, O2 binds more easily, stabilizes the R state

Question 9

Bohr effect

Answer 9

An increase in CO2 conc and decrease in pH shift the curve to the right, drops off more O2

Question 10

BPG

Answer 10

Binds in the pocket of the subunits and shifts the curve to the right, stimulating drop off of Oo2

Question 11

Fetal hemoglobin

Answer 11

Gamma subunit replaces beta, making a2G2

Question 12

Mechanism which HbF picks up O2

Answer 12

Does not bind BPG as well, curve shifts to the left, R-state is stabilized

Question 13

Sickle cell anemia

Answer 13

HbS, causes the clogging of capillaries, results because of glutamate to valine on b subunit creating hydrophobic “pocket”

Question 14

Methemoglobinemia

Answer 14

Occurs when the heme group is oxidized to +3 state, happens when you ingest nitrates or nitrites, or acquired