The respiratory system consists of the nose, pharynx, larynx, trachea, bronchi and lungs which work together to bring oxygen into the body through air pipes and remove the waste carbon dioxide through small air sacs in the lungs called alveoli. The system allows for oxygen to enter the bloodstream and carbon dioxide to leave from the blood out of the body. When issues arise in the respiratory system, such as an infection like pneumonia, it can cause difficulty getting oxygen and removing carbon dioxide, leading to common symptoms of breathlessness, cough and chest pain.