The trachea or wind pipe is the tube in air breathing vertebrates that conducts air from the throat to bronchi. It is strengthened with incomplete rings of cartilage. It originates from laryngopharynx, the lowermost or interiormost part of the pharynx. Pharynx (throat) is divided into three parts, the nasopharynx (nasal part of the pharynx) which lies behind the nasal cavities, above the soft palate, the oropharynx (oral part of the pharynx) which lies behind the oral cavity (buccal cavity) and the laryngopharynx (laryngeal part of the pharynx).