This document outlines and compares the circulatory systems of insects, fish, amphibians, and humans. It shows that insects have an open circulatory system while fish, amphibians and humans have closed circulatory systems. Within closed systems, fish have a single circuit system while amphibians have an incomplete double circuit system and humans have a complete double circuit system.

1. Circulatory Systems in
Insects, Fish, Amphibians
and Humans

2. Circulatory
System
Closed
Circulatory
System
Single
Eg. : Fish
Open Circulatory
System
Eg. : Insects
Double
Complete
Eg. : Human
Incomplet
e
Eg. :
Amphibian

4. Open Circulatory
System
Eg. : Insects

5. Closed
Circulatory
System

6. Single
Eg. : Fish

7. Single
Eg. : Fish

8. Incomplet
e
Eg. :
Amphibian

9. Incomplet
e
Eg. :
Amphibian

10. Incomplet
e
Eg. :
Amphibian

11. Complete
Eg. : Human

12. Complete
Eg. : Human

13. Complete
Eg. : Human

14. Complete
Eg. : Human