<P> Pharyngeal cancer is a cancer that originates in the neck and / or throat, and can cause serious clinical problems . </P> <P> Waldeyer's tonsillar ring is an anatomical term collectively describing the annular arrangement of lymphoid tissue in the pharynx . Waldeyer's ring circumscribes the naso - and oropharynx, with some of its tonsillar tissue located above and some below the soft palate (and to the back of the oral cavity). It's believed that, Waldeyer's ring prevents the invasion of microorganisms from going into the air and food passages and this helps in the defense mechanism of the respiratory and alimentary systems . </P> <P> The word pharynx (pronounced / ˈfærɪŋks /) is derived from the Greek φάρυγξ phárynx, meaning "throat". Its plural form is pharynges / fəˈrɪndʒiːz / or pharynxes / ˈfærɪŋksəz /, and its adjective form is pharyngeal (/ ˌfærɪnˈdʒiːəl / or / fəˈrɪndʒiəl /). </P> <P> All vertebrates have a pharynx, used in both feeding and respiration . The pharynx arises during development in all vertebrates through a series of six or more outpocketings on the lateral sides of the head . These outpocketings are pharyngeal arches, and they give rise to a number of different structures in the skeletal, muscular and circulatory systems . The structure of the pharynx varies across the vertebrates . It differs in dogs, horses and ruminants . In dogs a single duct connects the nasopharynx to the nasal cavity . The tonsils are a compact mass which point away from the lumen of the pharynx . In the horse the auditory tube opens into the guttural pouch and the tonsils are diffuse and raised slightly . Horses are unable to breathe through the mouth as the free apex of the rostral epiglottis lies dorsal to the soft palate in a normal horse . In ruminants the tonsils are a compact mass which point towards the lumen of the pharynx . </P>

What is the common name of the pharynx