Final answer:
Pneumothorax is the condition where air in the pleural space causes the lung to collapse, different from emphysema, bronchitis, and asthma, which affect the lungs in other ways.
Step-by-step explanation:
The condition in which air in the pleural space causes the lung to collapse is known as pneumothorax. Pneumothorax occurs when air enters the space between the lung and the chest wall, resulting in the lung collapsing due to the loss of negative pressure. This can happen spontaneously, often related to subtle abnormalities in connective tissue, or result from trauma or other conditions.
Other lung conditions mentioned such as emphysema, bronchitis, and asthma involve different mechanisms. Emphysema, for instance, is characterized by the destruction of the walls of the alveoli, leading to decreased gas exchange, and is generally caused by tobacco smoking. In the case of bronchitis and chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis or emphysema, the lung changes include a breakdown of connective tissues, reducing the number and elasticity of alveoli which leads to trapped air in the lungs and hampered gas exchange. Asthma, on the other hand, is marked by inflammation triggered by environmental factors leading to obstruction of the airways.