GENERAL HISTOLOGY

Detailed explanation-1: -Alveolar macrophages localize at the boundary between the lungs and external environment. Macrophages are responsible for the removal of particles, such as dust or microorganisms, from the respiratory surfaces by phagocytosis.

Detailed explanation-2: -Alveolar macrophages play an important role in scavenging microbes such as viruses, bacteria, fungi, inhaled environmental particles like coal, silica, asbestos, tissue debris, and cancer cells.

Detailed explanation-3: -Each alveolus is lined by simple squamous epithelium, exceedingly thin to facilitate diffusion of oxygen while still forming an epithelial barrier between the outside air and the internal body fluids.

Detailed explanation-4: -Alveolar macrophages are the primary phagocytes of the innate immune system, clearing the air spaces of infectious, toxic, or allergic particles that have evaded the mechanical defenses of the respiratory tract, such as the nasal passages, the glottis, and the mucociliary transport system.