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.
The heart, arteries and veins are all part of the circulatory system. Blood moves through the heart and travels along arteries to get to the other organs in the body. Blood then travels back to the heart through the veins.Arteries contain blood that has lots of oxygen in it. Veins contain blood with less oxygen in it.lood moves through the heart and travels along arteries to get to the other organs in the body. Blood then travels back to the heart through the veins. Arteries contain blood that has lots of oxygen in it. Veins contain blood with less oxygen in it.