OPEN SYSTEM CIRCULATION | CLOSE SYSTEM CIRCULATION |
Heart not chambered | Chambered heart |
Few short blood vessels for a short distance and for a while | Blood flows in long vessels all the time |
Blood flows into coelum for some time | Blood remains in vessels throughout |
No capillaries | Presence of complex network of capillaries |
Organs are bathed by blood | Organs are supplied with blood by vessels |