Tutorial Answer 4

All of these factors affect the normal growth and development of tissues during childhood development, and the maintenance of tissues during adulthood. People with sickle cell disease never have adequate oxygen delivery to their tissues because sickled cells do not transport oxygen at all; and because sickled cells either block small vessels or are removed from the system by the spleen, thus lowering the number of red blood cells in circulation. The effects are universal throughout the body. Particularly affected, however, are organs such as the heart, which becomes enlarged in an attempt to meet the circulatory demands of the oxygen-deprived tissues; the kidney, whose fine capillary filtration system becomes obstructed by sickled cells; and the spleen, where old (or sickled) red blood cells are taken out of circulation and degraded.