Cockroach - Circulatory System

The circulatory system in cockroaches is an open type system, which means that the blood flows freely within the body cavity called haemocoel, and not confined within blood vessels.

Haemocoel

The haemocoel is the main body cavity of insects, which is filled with blood called haemolymph. It provides mechanical support to the body, and also serves as a hydrostatic skeleton.

Heart

The heart of cockroach is a long, tubular structure, located dorsally in the abdomen. It is divided into 13 chambers, each having a pair of lateral ostia and a posterior ostium. The lateral ostia allow the blood to enter the heart, while the posterior ostium pumps the blood out into the haemocoel.

Vessels

The haemocoel is divided into three regions: anterior, middle and posterior, and there are vessels that connect them. The anterior region receives blood from the head and thorax, while the posterior region collects blood from the abdomen.

Function

The circulatory system of cockroach transports oxygen, nutrients, and wastes throughout the body. It also helps in maintaining the water balance, and acts as a defence mechanism against pathogens.

Conclusion

The circulatory system in cockroach is an open type system, where the blood flows freely within the haemocoel. The heart pumps the blood into the haemocoel, which transports oxygen, nutrients, and wastes throughout the body.

The circulatory system of cockroach is open type.Here the blood flows partly through vessels and partly through thin walled haemocoelomic spaces called Sinuses and Lacunae.The sinuses are large body cavities and the blood present there is called haemoglobin.The blood vascular system of cockroach consists of Heart,a blood vessel called the aorta & haemocoel but no capillaries or veins.