1. Blood circulates throughout
the body in specific routes or
paths called circuits.

2. Pulmonary circulation is the
blood circuit between the
heart and the lungs.

3. Systematic circulation is the
blood circuit between the
heart and various organs of
the body.

4. Portal circulation is a special
blood circuit from the
arteries through the main
organs of digestion.

5. Renal circulation is the
blood circuit through the
capillaries to the kidneys.

6. Coronary circulation is the
blood circuit within the
heart.