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
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. Well also
study the human heart and circulation, and end by considering the
causes and effects of cardiovascular disease.