In an open circulatory system, blood is ________.
A) always inside of vessels and is under higher pressure than in closed circulatory systems
B) not always confined to blood vessels and is under higher pressure than in closed circulatory systems
C) always inside of vessels and is under lower pressure than in closed circulatory systems
D) not always confined to blood vessels and is under lower pressure than in closed circulatory systems

Question

Quizplus · Accepted Answer

In an open circulatory system, blood is not always confined to blood vessels and is under lower pressure than in closed circulatory systems. Open circulatory systems are found in arthropods and mollusks where the blood, called hemolymph, is pumped into a hemocoel, which is a cavity within the body that surrounds the organs. The hemolymph directly bathes the organs and tissues, and exchanges of gases and nutrients occur through diffusion. The lack of vessels and lower pressure in open circulatory systems limit the efficacy of oxygen and nutrient delivery compared to closed circulatory systems.

In an Open Circulatory System, Blood Is ________