The circulatory system of cockroach:
- It is an open type. Blood vessels are poorly developed and open into haemocoel or open spaces.
- Body fluid present in hemocoel is also known as hemolymph.
- Blood is colorless as there is no respiratory pigment.
- Blood doesn't perform the function of transporting gases.
- Cockroach possesses 13- chambered tubular, muscular, elongated and neurogenic heart.
- Blood circulation in cockroach is maintained by wing-shaped alary muscles (involuntary).