o2+co2 transport in the blood. Flashcards
(21 cards)
equation for OXYHAEMOGLOBIN
4o2 + Hb -> Hb’4O2+
structure of haemoglobin
4 haem groups each with an Fe2+ ion
first haem group
changes shape for binding of second one
second haem
easier because of 1st, also changes shape
third haem
easier because of 2nd, does NOT change shape
4th haem
hard because 3rd does not change
needs a large increase in po2
what is the partial pressure of o2
the pressure it would exert if it was the only one present
o2 is 21% of atmosphere so pp= 21kpa
what curve represents the o2 affinity
sigmoid curve/ s shaped
what is the process of fe binding with o2 called
cooperative binding
describe the sigmoid curve at high po2
o2 affinity is high at high po2 but reduces as po2 decreases
describe sigmoid curve at lower po2
high po2, o2 affinity too low, o2 readily released
lower po2, o2 affinity too high, no release
foetal haemoglobin
fetal hb needs to absorb o2 from maternal
2 pp chains differ so it has a higher affinity
foetal haemoglobin curve is
to the left of adult human
lugworm haemoglobin
burrows in low o2 sand and has a low metabolic rate
lugworm curve
very to the left
increase in altitude=
decrease in partial pressure of o2
more co2
more readily o2 released
BECAUSE at any po2, the hb is less saturated so the curve shifts to the RIGHT
curve shifting to the right due to more co2 known as
bohr shift/effect
co2 is transported as with %
plasma 5
hco3- 85
carbaminohaemoglobin 10
process of co2 into o2 in rbc
co2 diffuses into rbc
carbonic anhydrase catalyses combination of h2o and co2 to create carbonic acid
carbonic acid dissolves into h+ and hco3- ions
hco3 ions diffuse out into plasma and bring chloride ions in
h+ causes hb.4o2 to disccosiate into o2 and hb
hb combines with h+=haemoglobinic acid
o2 diffuses out
chloride shift
chloride ions diffuse into red blood cell to maintain electrical neutrality from the removal of hco3- ions
