Lecture 15 - Oxygen Transport - midterm 2 Flashcards
1 litre of arterial blood (at sea level) contains how many ml of dissolved o2
3ml
The heart pumps _____ of blood/min
5 L
A total of ________ of dissolved O2 is carried in the blood/min
15 ml
At rest we need around __________ for basal function
250ml O2/min
The 15ml of dissolved O2 per min is not enough to live
We need a way to make up the extra 235 ml/min of O2 (hemoglobin)
To make up for the additional 235 ml/min of oxygen needed, the body relies on the oxygen-carrying capacity of hemoglobin.
Therefore, the additional 235 ml/min of oxygen needed can be supplied by an increase in the amount of hemoglobin circulating in the body or an increase in the amount of oxygen bound to hemoglobin.
1 litre of arterial blood (at sea level) contains how many ml of dissolved CO2
30 ml of dissolved CO2 (10x more than oxygen)
This is due to the solubility coefficient (k); CO2 is far more soluble than O2
how many heme groups/molecule are there
4 heme groups/molecule
every heme group can bind ____ molecules of O2
4
how any O2 molecules per hb
4 O2 molecules/Hb
what give RBC their red colour
Hb
When O2 is bound to Hb it has no pressure. true or false
true
Hb is around __________of blood (g/ml)
15g/100ml
Heart pumps around ________ blood/min
5000 ml/min
In the pulmonary capillaries why do we want to keep the amount of dissolved O2 as low as possible in the plasma and RBC
gives more time for oxygen to move from the alveoli to the RBC} better diffusion
what is The function of Hb in the RBC
to keep the dissolved O2 content in the RBC and plasma as low as possible for as long as possible
HBO2 has no pressure, only the O2 dissolved has pressure. true or false
true
In the tissues (O2 going from blood to cells), we want to keep the dissolved O2 in the plasma and RBC as high as possible for as long as possible. why?
allows diffusion to occur
The partial pressure of O2 in the cells and interstitial fluid is _______, and _____ in the plasma and the RBC
low
high
what is the purpose of hb in the blood
By putting Hb in the blood, you get a pressure gradient (the pressure in the alveoli becomes higher than the pressure in the blood; this leads to diffusion and movement from high to low)
Hb allows the partial pressure of O2 in the blood to remain low compared to the alveoli, so diffusion can occur
Hb acts as a ‘sink’ to keep PO2 as low as possible and maintains a gradient for diffusion of O2
what happens when o2 comes in
As O2 comes in, the Hb molecules become fully saturated and lead to an equilibrium (equal amount of O2 molecules in the alveoli and dissolved O2 molecules in the blood) (the partial pressure of O2 in the alveoli and in the blood will always eventually reach equilibrium)
