Blood vascular system:

It has a fluid called blood, pumped by heart in all tissue through many tubes (blood vessels). This system is called cardiovascular system. It is further of two types:

Open circulatory system: Here, blood is in direct contact within the tissues, its flow is slow with low pressure. Arthropods and mollusks have this type of circulation. And pigment if present is dissolved in plasma.

Closed circulatory system: Here, blood flows in special blood vessels, its flow is fast with high pressure. Annelids and vertebrates have this type of circulation. Pigment if present is mostly occurs in RBCs, but also present in plasma.