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Study Guides
The Circulatory System
Circulatory systems range from systems that rely on simple chemical diffusion up to the complex arrangement of arteries, veins and four-chambered heart of birds and mammals.
Animal circulatory systems perform a number of functions: they deliver oxygen and nutrients to cells, they remove waste products from cells and tissues, and they distribute heat and hormones.
In this Lesson we'll explore the different types of circulatory system and the components of these systems: heart, blood vessels and blood itself. We’ll also study the human heart and circulation, and end by considering the causes and effects of cardiovascular disease.