how Circulation works |Circulation and circulatory system overview| Chapter circulation Video 1 скачать в хорошем качестве

how Circulation works |Circulation and circulatory system overview| Chapter circulation Video 1

Blood circulation The circulation of blood refers to its continual flow from the heart, through branching arteries, to reach and traverse the microscopic vessels in all parts of the body, reconverging in the veins and returning to the heart, to flow thence through the lungs and back to the heart to start the circuit again. This uninterrupted movement of the blood is necessary to maintain the supply of oxygen from the lungs and nutrients from the gut, as well as for the distribution of hormones, many other chemicals, water, and heat, and the delivery of waste for excretion. The 5 litres of blood contained in the blood vessels of a typical adult at rest complete the circuit in about one minute: the blood recirculates 1500 times each day even without any exercise to speed it up. #BloodCirculation #OpenAndClosedCirculatorySystem #MechanismOfCirculation