Located in plant cells are large irregular shaped green structures called chloroplasts. They are green because they contain a green pigment called chlorophyll.
An open circulatory system is a type of circulatory system in which nutrients and waste are moved through the body with the assistance of a fluid which flows freely through the body cavity, rather than being contained in veins.
Other organisms have a closed circulatory system where transport is contained within a closed circuit of vessels. This type of system is common among larger organisms, including humans, and has many advantages, including quicker and more controlled movement of blood.lood then freely flows back into vessels that direct the blood back to the heart. Overall, you could describe an open circulatory system as being more free flowing and passive. There are many organisms that have open circulatory systems, including grasshoppers, snails and clams.