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.
Arteries are blood vessels that carry blood from your heart to different parts of your body. Raynaud's sometimes is called a disease, syndrome, or phenomenon. The disorder is marked by brief episodes of vasospasm (VA-so-spazm), which is a narrowing of the blood vessels. Vasospasm of the arteries reduces blood flow to the fingers and toes. In people who have Raynaud's, the disorder usually affects the fingers. In about 40 percent of people who have Raynaud's, it affects the toes. Rarely, the disorder affects the nose, ears, nipples, and lips.