Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation of the joints. Autoimmune diseases are illnesses that occur when the body's tissues are mistakenly attacked by their own immune system.
What role did the bison or buffalo play in the culture of the Plains Indians? The bison were an important source of fur, food, and shelter for the Plains Indians. They used every part of the animals they killed. Bison were also an important part of their culture.
The bison, a relative of cattle, is native to the North American prairie. Bison are the largest land mammals in North America, but they have small, pointed hooves. These hooves turn up the soil, just like a plow does.