Final answer:
In a closed circulatory system, blood is contained inside blood vessels and circulates unidirectionally, allowing for efficient transportation of nutrients and waste products. In an open circulatory system, blood is not enclosed in blood vessels but circulates within a body cavity, providing gas and nutrient exchange.
Step-by-step explanation:
In a closed circulatory system, blood is contained inside blood vessels and circulates unidirectionally from the heart around the systemic circulatory route, then returns to the heart.
This system is present in most vertebrates and some invertebrates. It allows for efficient transportation of nutrients and waste products, but requires more energy to operate compared to an open system.
In an open circulatory system, blood is not enclosed in blood vessels but is pumped into a cavity called a hemocoel.
The blood, called hemolymph, mixes with the interstitial fluid and circulates within the body cavity, providing gas and nutrient exchange. This system is found in arthropods and some mollusks. It is less energy-intensive but has limitations on the amount of blood that can be transported to metabolically active organs.