The showy sunflower, with its bright yellow petals radiating from a dark hub of seeds, can reach up to 12 inches in diameter. This tall, rangy plant is thought to be so named because its flowers resemble the sun, and because they twist on their stems to follow the sun throughout the day. Sunflowers were cultivated by the Indians of the Americas long before Europeans discovered them. Today, the Russians are one of the largest sunflower seed producers in the world. Though it's the state flower of Kansas, the largest United States sunflower producers are California, Minnesota and North Dakota. The seeds have a hard black-and-white striped shell that must be removed. Sunflower seeds can be dried or roasted (either in or out of the shell), and are sold either plain or salted. They can be eaten as a snack, used in salads or sandwiches or added to a variety of cooked dishes or baked goods. The iron-rich sunflower seeds are, by weight, 47 percent fat and 24 percent protein. The pale yellow, delicately-flavored sunflower-seed oil extracted from the seeds is very high in polyunsaturated fat and low in saturated fat. Though it has a relatively low smoke point, sunflower-seed oil is used in cooking as well as for salad dressings. See also fats and oils.