The species theory, polygenism, held that human races were of different lineages and suggested a hierarchy outlined in the Chain of Being that positioned Africans between man and lower primates.
No, they are involved in the Circulatory System which is responsible for pumping and channelling blood to and from the body and lungs with heart, blood and blood vessels. no veins are not considered an organ because they are a grouping of different tissues like a organ.
There are three types of blood vessels: arteries, veins and capillaries. The heart is an organ made of cardiac muscle and it acts like a pump. The muscles of the heart contract and pump blood away from the heart (through the aorta) and to the tissues of the body.