1 Colored Egg Layer Chickens. The Araucana is a pure breed of chicken originating in Chile. 2  Ameraucana chickens were developed in the 1970âs in the United States from Araucanas. They were developed as a practical barnyard fowl that laid pastel shelled eggs, but without some of the limiting genetic factors related to rumplessness and tufts.
sex chromosome. a chromosome, differing in shape or function from other chromosomes, that determines the sex of an individual.
Essay on Sex Chromosomes. In humans, the sex of an individual is determined by the type of sex chromosomes a person has. Most men have an X chromosome from their mother and a Y chromosome from their father. Most women receive an X chromosome from their mother and an X chromosome from their father.