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Key Terms

apoptosis
cellular death
asthma
a chronic disease process clinically characterized by recurrent inflammation and airway narrowing, limiting gas exchange in the lungs
chronic bronchitis
when the airway lining experiences too much inflammation, leading to increased mucus production
chronic obstructive pulmonary disease (COPD)
chronic pulmonary diseases known as emphysema and chronic bronchitis
emphysema
damage between the walls in the alveoli that exchange gas in the lungs
free radicals
compounds that take part in the cellular destruction mechanism of phagocytosis through macrophages and granulocytes
hyperemia
a condition that occurs as a result of a higher-than-normal blood flow
pneumonia
a condition that leads to inflammation of the lung parenchyma caused by infection, chronic pulmonary diseases, ventilator use, or aspiration; pneumonia can lead to chronic damage, such as lung fibrosis
pulmonary embolism
a thrombus that becomes dislodged and travels to the lungs, preventing the natural flow of blood within the pulmonary artery or its branches
pulmonary fibrosis
scarring of the lung tissues that causes stiffening, limiting lung function
respiratory tract infections (RTI)
microorganisms that infect the upper and lower respiratory tract and lead to symptoms such as fever, sore throat, cough, chest pain, dyspnea, and myalgia
rhinitis
inflammation that causes symptoms such as nasal congestion, runny nose, sneezing, and postnasal drip
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