Genetics is the study of the biological processes involved in transmitting the unique characteristics of an organism to its offspring. Discovering the genetic principles and mechanisms that account for growth, senescence, and heredity has been a great accomplishment of modern science. Gregor Mendel’s studies of pea plants revealed the concept of genes and the rules for the inheritance of traits. Today it is understood that those rules are based on the chemical composition and structure of DNA. Students in grade seven will learn some of those rules, which will serve as a foundation for high school biological sciences.