Blood is a suspension.
In a suspension, solute-like particles
of a substance are blended with a solvent-like fluid but are not dissolved. Blood
is a suspension of blood cells and platelets. It contains large particles large
enough ( to settle) for sedimentation.
Erythrocytes are cells that
transport oxygen from the lungs to the body It also removes and transports
carbon dioxide from body tissues to the lungs. The average adult has
approximately 5million cells/ul. Its production is  controlled by erythropoietin. Erythropoietin
is produced by the kidneys.
