Homeostasis in the Cardiovascular System

While homeostasis for body temperature seeks to keep the core temperature constant within about 1°C, homeostasis for the body's blood supply must be a much more dynamic system. The operating principle there must be to provide adequate blood supply to all tissues, regardless of the level and nature of the body's activity. This involves a continual process of redirecting and adjusting of the volume flowrate of the blood in response to changes in activity. A table of typical blood flow rates on the ER Services site was used for the illustration below.

In a progression from a resting state to maximal exercise, the volume flowrate may increase by about a factor of three. The most dramatic increase in the flowrate is to the skeletal muscles, which may be on the order of a tenfold increase. Accompanying such an increase in muscular effort will be a major increase in bloodflow to peripheral blood vessels, formally called the integument. This is associated with the need to bing more blood to the body's surface for the dissipation of heat produced by the higher level of mechanical activity. This engages the physiological mechanisms for temperature control of the body.

One of the most interesting aspects of bloodflow homeostasis is the maintaining of the bloodflow to the brain within very narrow limits, even with a tripling of overall bloodflow.