Odviously-it's-a-closed-system-what-really-come-in-and-out-of-the-earths-crusts...
closed
Closed (I think. All vertebrates I know of have a closed system)
They have open circulatory system.
A humans circulatory system is closed. Large creatures tend to have a closed system, while smaller creatures like insects and crustaceans have open circulatory systems. Closed is when there are vessels and the blood stays there. Open is when blood floats around the body. Hope it helps:)
The light bulb is a closed system: no mass transfer.
Closed System
closed.
Closed System
closed system
closed system
Amphibians have closed circulatory system Closed
closed circulatory system
Odviously-it's-a-closed-system-what-really-come-in-and-out-of-the-earths-crusts...
A battery-operated wrist watch is a closed system. A wind-up wrist watch is an open system.
closed
closed!