Because its blood moves through vessels, or tubes in the body. In the head of the worm two large vessels meet and form five pairs of hearts which pumps blood through the vessels.
closed
closed circulatory system
open!
Earthworms have a closed circulatory system. This means that their blood is contained within vessels as it circulates throughout the body, allowing for more efficient transport of nutrients and oxygen. The blood is pumped by a series of muscular structures called aortic arches, which act like hearts. This system enables earthworms to maintain a more regulated flow of blood compared to open circulatory systems.
The light bulb is a closed system: no mass transfer.
an open circulatory system
Closed System
Earthworms have a closed circulatory system. Blood is pumped throughout its body by ringed blood vessels. An open circulatory system is not contained in vessels. In a closed circulatory system oxygen is carried in blood! hope this helps=)
Amphibians have closed circulatory system Closed
Both crayfish and earthworms have a circulatory system that is responsible for transporting nutrients and oxygen throughout their bodies. They utilize a system of blood vessels, although crayfish have an open circulatory system while earthworms possess a closed circulatory system. Additionally, both organisms rely on hemolymph (in crayfish) and blood (in earthworms) to carry essential substances, highlighting a fundamental similarity in their roles despite structural differences.
A battery-operated wrist watch is a closed system. A wind-up wrist watch is an open system.
Closed