Your circulatory system is made up of three parts: the heart, blood vessels and the blood itself. Your heart keeps all the blood in your circulatory system flowing. The blood travels through a ...

Between 10 and 20 per cent of the Western adult population has high blood pressure. The sensation of pins and needles is caused by an impairment of blood circulation.

The changes in metabolic activity associated with endothermy and the change from gill to lung respiration has led to changes in vertebrate circulatory systems. Veins between two capillary networks are ...