The term INHERITANCE UNIT can be broken down into two parts: GENE (4 letters) and UNIT. GENE is a term used in genetics to refer to a UNIT of heredity, which is passed from parent to offspring and contains the information needed to determine an organism's traits. UNIT refers to a single entity or component of a larger system, such as a family UNIT or a business UNIT. Together, the two terms form the concept of an INHERITANCE UNIT, which is a group of people who share a common genetic heritage and are related by blood.