Which organ is primarily affected by respiratory diseases?

The primary organ affected by respiratory diseases is the lung. Respiratory diseases encompass a variety of conditions that impact the airways and lung tissue, thereby affecting breathing and gas exchange. Diseases such as asthma, chronic obstructive pulmonary disease (COPD), pneumonia, and lung cancer specifically target the lungs, leading to inflammation, obstruction, or scarring of lung tissue.

Understanding the role of the lungs in the respiratory system is essential since they are responsible for inhaling oxygen from the atmosphere and expelling carbon dioxide, a waste product of metabolism. Any disease that compromises lung function can significantly impact overall health and oxygen supply to the body.

In contrast, while the heart, liver, and kidneys can all be indirectly affected by respiratory conditions (for example, the heart may work harder if the lungs are not providing adequate oxygen), they are not the primary organs involved in these diseases. The direct link between respiratory ailments and lung function makes the lungs the correct answer.