The Biopsychosocial Model is an important approach to understanding health, illness, and human behaviour by integrating biological, psychological, and social factors. In the application of social psychology, this model is particularly useful because it explains how individual behaviour and mental health are influenced not only by biological processes but also by thoughts, emotions, relationships, social groups, and the wider social environment. It provides a comprehensive alternative to approaches that explain health problems only through biological causes. The biological dimension focuses on physical and physiological factors affecting health and behaviour. These include genetic inheritance, brain functioning, hormones, immune responses, nutrition, sleep, physical illness, and substance use. For example, depression may be associated