Personality refers to the specific set of cognition, behaviors, and emotional patterns that originate from biological and environmental factors. Biological factors are essential in determining the personality of an individual because personality traits are hereditary. Every human being inherits similar sets of natural capacities and needs. People tend to resemble the physical appearances and intelligence of the parents. The nervous system, the duchess glands, and the organic drivers have a great contribution to personality. The nervous system affects the talent and intelligence of a human being. Hormones affect how personality grows. An individual’s behavior can be genetically influenced; hence people of a similar family will have similar personality traits. Therefore it clear that biological factors are important in determining the personality of a person.