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.
1 The largest internal organ is the liver. 2  It is also the heaviest organ, with an average of 1.6 kilograms (3.5 pounds). 3  The largest external organ, which is also the largest organ in general, is the skin. 4  The longest muscle is the sartorius muscle in the thigh. The longest bone in the human body is the femur. 2  The largest artery is the aorta and the largest vein is the inferior vena cava. 3  The largest internal organ is the liver. 4  It is also the heaviest organ, with an average of 1.6 kilograms (3.5 pounds).