Problem:
Respond to DQ in APA format and in paragraph form. The immune system's defenses can be thought of as layers. The primary lines of defense are our body's initial barriers to infection, including the skin, mucous membranes, and secretions like saliva, stomach acid, tears and normal flora (Banasik, 2021). These provide a physical and chemical shield to keep pathogens out. In contrast, the secondary line of defense becomes activated once pathogens bypass these initial barriers. This response includes inflammation, fever, phagocytic cells such as macrophages and neutrophils, and other immune responses that work to eliminate invading organisms (Melo Silva & Sigal, 2024). The secondary defense system responds rapidly but nonspecifically, making it part of the body's innate immune response. Factors that can interfere with these immune mechanisms include poor nutrition, chronic stress, lack of sleep, immunosuppressive medications, smoking, and chronic diseases, all of which can impair immune functioning and increase susceptibility to illness (Banasik, 2021). The effectiveness of immune defenses also varies depending on age and overall health. In children, the immune system is still developing, making them more vulnerable to infections because immune memory and antibody production are not yet fully mature. Young children also rely partly on passive immunity received from maternal antibodies, particularly during infancy. Need Assignment Help?