1 Biological factors play a role in behavior. Twin studies have been used to estimate the magnitude of behavioral genetics. These studies often employ a variety of psychological assessments. How did psychometric testing develop as a branch of psychology? What have been the beneficial effects of psychometric testing? How have psychometric tests been used to promote eugenics? 2 We spend approximately one third of our lives sleeping, and yet, we know very little about why we sleep. What is sleep? Provide a brief definition of sleep. What are the different ways in which animals sleep? Does phylogeny provide clues about the function or importance of sleep? Why do we sleep? Provide evidence to support your answer. 3 Describe the work of these psychologists in a historical context. Expanding on the work of Maslow and Rogers, Seligman and Csikszentmihalyi sought to move psychology beyond treatment of pathology, weakness, and damage. Briefly describe the contributions of each of these psychologists to humanistic psychology. What is the value of Maslow's hierarchy of needs? What did Rogers mean by "self-actualization"? How did World War II influence Seligman's approach to psychology? What is a "flow