1 adj Social means relating to society or to the way society is organized. ADJ n. ...the worst effects of unemployment, low pay and other social problems., ...long-term social change., ...changing social attitudes., ...the tightly woven social fabric of small towns., ...research into housing and social policy.
The human circulatory system (simplified). Red indicates oxygenated blood carried in arteries, blue indicates deoxygenated blood carried in veins. Capillaries, which join the arteries and veins, and the lymphatic vessels are not shown.
The essential components of the human cardiovascular system are the heart, blood and blood vessels. It includes the pulmonary circulation, a loop through the lungs where blood is oxygenated; and the systemic circulation, a loop through the rest of the body to provide oxygenated blood. The systemic circulation can also be seen to function in two partsâa macrocirculation and a microcirculation.