Final answer:
A closed circulatory system has blood contained within vessels and separate from interstitial fluid which allows efficient transport of nutrients and waste. It can vary by species, with mammals and birds having a four-chambered heart and fish, amphibians, and reptiles having two or three-chambered hearts.
Step-by-step explanation:
A closed circulatory system features blood that is entirely contained within blood vessels, maintaining separation from the body’s interstitial fluid. This system allows for a more efficient and controlled way to transport nutrients and waste products throughout the organism. Vertebrates exhibit different types of closed circulatory systems based on the number of heart chambers; for instance, mammals and birds have a four-chambered heart with double circulation, ensuring minimal mixing of oxygenated and deoxygenated blood, whereas fish have a two-chambered heart, and amphibians and reptiles typically have a three-chambered heart with varying degrees of blood mixing.