This comprehensive review aims to provide a deep insight into the fascinating field of biophysics in living organisms through the study of model fluid interfaces that mimic specific lipid-based structures with biophysical relevance. By delving into the study of these physiological fluid interfaces, we can unravel crucial aspects of their behavior, lateral organization, and functions. Through specific examples, we will uncover the intricate dynamics at play and shed light on potential pathogenic conditions that may result from alterations in these interfaces. A deeper understanding of these aspects can lead to the emergence of novel technologies and medical advances, potentially leading to the development of innovative treatments and diagnostic tools.