Anatomy and Physiology II Practice Test

The upper respiratory tract is primarily responsible for the initial stages of breathing, including the filtering, warming, and humidifying of air before it enters the lower respiratory tract. The components that comprise the upper respiratory tract include the pharynx, larynx, and nose.

The pharynx serves as a passageway for air from the nasal cavity to the larynx, as well as for food from the mouth to the esophagus. It plays a crucial role in both respiration and digestion. The larynx, also known as the voice box, is located below the pharynx and serves several important functions, including protecting the trachea against food aspiration and facilitating phonation, or sound production. Finally, the nose, which includes the external nasal structures and nasal cavity, is the primary entry point for air. It houses the olfactory receptors for smell and contains mucus and cilia that help trap dust and pathogens.

In contrast, the other options include components that belong to the lower respiratory tract or are not specific to the upper respiratory system. For example, the trachea, bronchi, and alveoli are part of the lower respiratory tract, responsible for air conduction, gas exchange, and ultimately bringing oxygen to the bloodstream. Understanding