The circulatory system is an important system in the body that plays an important role to circulate essential ions and nutrients in all the parts of the body.
This system helps to transport and circulate carbon dioxide, oxygen, and all the essential nutrients to all parts of the body.
Different organisms have different circulatory systems.
Two types of circulatory systems include the open and closed circulatory systems.
Open circulatory system:
This system is mainly present in invertebrates.
In this system, the blood flows easily through the cavities and there are no vessels, arteries, and veins present to conduct the blood.
Blood is not conducted by the blood vessels and is pumped into an open cavity called a hemocoel, when blood enters the hemocoel it gets mixed with the interstitial fluid.
It is present in all invertebrates.
Closed circulatory system :
This system is present in vertebrates and a few invertebrates such as earthworms.
This system comprises arteries, veins, vessels, heart, and lungs.
The heart pumps blood into the larger blood vessels so that it can reach the tissues and organs but between smaller vessels called capillaries and tissues, gases are exchanged.