haemoglobin

Question 1

what does oxygen-Hb dissociation curve show

Answer 1

O2 carrying capacity of Hb at different pO2

Question 2

shape of oxygen-Hb dissociation curve and reason

Answer 2

sigmoid shape; binding of one O2 molecule facilitates second molecule binding (cooperative binding)

Question 3

what is P50 and significance

Answer 3

partial pressure of O2 at which Hb is half saturated with O2, gives affinity of Hb variants for O2

Question 4

oxygen-Hb dissociation curve: arterial vs venous

Answer 4

arterial is fully saturated, venous is 75% saturated (much lower partial pressure of O2)

Question 5

oxygen-Hb dissociation curve: haemoglobin and situations which cause shift left and effect on oxygen delivery

Answer 5

HbF, less 2,3-DPG, higher pH, so binds oxygen more readily (greater O2 affinity) and gives up oxygen less readily

Question 6

oxygen-Hb dissociation curve: haemoglobin and situations which cause shift right and effect on oxygen delivery

Answer 6

HbS, more 2,3-DPG, lower pH (high H+ and CO2), so binds O2 less readily (lesser O2 affinity) and gives up oxygen more readily

Question 7

what does normal position of oxygen-Hb dissociation curve depend on

Answer 7

[2,3-DPG], pH, CO2 in red blood cells, structure of Hb