See Flow for more details on Hagen-Poiseuille's law and laminar vs turbulent flow.
Flow = pressure / resistance
Resistance = 8nl/r4pi
Resistance is proportional to viscosity, not density.
Resistance is proportional to flow.
Resistance is proportional to density, not viscosity
Apparent viscosity varies with haematocrit ratio.
Haematocrit decreases progressively as vessel diameters reduces below 300 micrometer.
--> RBCs tend to accumulate in the faster axial stream of blood
--> RBCs moves at greater speed in axial stream
--> Relative haematocrit ratio decreased
--> Apparent viscosity decreased
* [BL8:p129]
Also, when flow decreases, cells tend to aggregate and increase viscosity.
When flow increases, viscosity decreases
--> "shear thinning"
Note:
Functional cardiac murmur in anaema is due to:
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