pneumonia directly affects which part of the body
Pneumonia Pneumonia is an inflammatory condition of the lung affecting primarily the small air sacs known as alveoli.[4][13] Typically symptoms include some combination of productive or dry cough, chest pain, fever, and trouble breathing.[2] Severity is variable.[2]
Mucus In the human respiratory system, mucus, also known as airway surface liquid (ASL), aids in the protection of the lungs by trapping foreign particles that enter them, in particular, through the nose, during normal breathing.[3] Further distinction exists between the superficial and cell-lining layers of ASL, which are known as mucus layer (ML) and pericilliary liquid layer (PCL), respectively.[4] "Phlegm" is a specialized term for mucus that is restricted to the respiratory tract, whereas the term "nasal mucus" describes secretions of the nasal passages.