Vascular shunting Flashcards
what is vascular shunting
the redistribution of cardiac output to where oxygen is needed most
where does more blood go to
the heart, the working muscles, the skin(to cool the body down), if the stomach is full more blood goes to the gut instead of working muscles for digestion
where does blood flow remain constant to
the brain remains constant
what is vasoconstriction and why does it happen
vasoconstriction is the narrowing of the blood vessels to reduce blood flow to the capillaries in the inactive muscles to redirect oxygenated blood to active muscles
what is vasodilation and why does it occcur
widening of the blood vessels to increase the flow of blood into the capillaries to increase oxygen to the working muscles
where do veins arteries and capillaries transport blood to?
veins - deoxygenated blood back to the heart
arteries- oxygenated blood around the body
capillaries- slows blood flow, exchange of nutrients one cell thick
what is oxyhemoglobin dissociation
97% of oxygen is transported through oxyhemoglobin 3% dissolves in blood plasma, when oxygen is released from oxyhemoglobin into the tissues
what is myoglobin
where oxygen is stored in the muscles as it has a higher affinity for oxygen than haemoglobin, the oxygen is used by mitochondria in muscle cells
what is the oxyhemoglobin dissociation curve
is a graphical representation of the relationship between the amount of oxygen bound to hemoglobin and the partial pressure of oxygen in the blood.
what is the bohr shift
when an increase in carbon dioxide in the blood and a decrease in pH results in a reduction in the affinity of haemoglobin for oxygen
which way does the S shaped curve shift and why
to the right as when muscles require more oxygen the dissociation of oxygen in the blood capillaries to the muscle tissue occurs more readily
what factors are responsible for the increase in the dissociation of oxygen from haemoglobin
increase in blood temperature, increase in partial pressure of carbon dioxide, a drop in pH(more Co2)
