Actors Ellen Pompeo, Sandra Oh, Katherine Heigl, Justin Chambers, and T.R. Knight reprised their roles as surgical interns Meredith Grey, Cristina Yang, Izzie Stevens, Alex Karev, and George O'Malley, respectively, continuing their expansive storylines as focal points throughout the season.
From Wikipedia, the free encyclopedia. In psychology, trait theory (also called dispositional theory) is an approach to the study of human personality. Trait theorists are primarily interested in the measurement of traits, which can be defined as habitual patterns of behavior, thought, and emotion.n some theories and systems, traits are something a person either has or does not have, but in many others traits are dimensions such as extraversion vs. introversion, with each person rating somewhere along this spectrum.
A phenotypic trait, or simply trait, is a distinct variant of a phenotypic characteristic of an organism that may be inherited, be environmentally determined or be a combination of the two. trait may be any single feature or quantifiable measurement of an organism. However, the most useful traits for genetic analysis are present in different forms in different individuals. A visible trait is the final product of many molecular and biochemical processes.