Search results
Results from the WOW.Com Content Network
The human nose is the first organ of the respiratory system. It is also the principal organ in the olfactory system. The shape of the nose is determined by the nasal bones and the nasal cartilages, including the nasal septum, which separates the nostrils and divides the nasal cavity into two.
The nasal septum is composed of four structures: Maxillary bone (the crest) Perpendicular plate of ethmoid bone. Septal nasal cartilage (ie, quandrangular cartilage) Vomer bone. The lowest part of the septum is a narrow strip of bone that projects from the maxilla and the palatine bones, and is the length of the septum.
Inside the nostrils of the vestibule are the nasal hair, which filter dust and other matter that are breathed in. The back of the cavity blends, via the choanae, into the nasopharynx .
The orientation of the nasal cartilages can produce different shapes and sizes of the nostrils and nasal cavities. For the most part, animals contain similar cartilage structures within the nose but vary in the number of different cartilage structures they have.
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose . Each has two surfaces and four borders.
Like other tetrapods, humans have two external nostrils (anterior nares) and two additional nostrils at the back of the nasal cavity, inside the head (posterior nares, posterior nasal apertures or choanae ). They also connect the nose to the throat (the nasopharynx), aiding in respiration.
Illustration of upper respiratory system. In anatomy, a nasal concha ( / ˈkɒnkə /; pl.: conchae; / ˈkɒnkiː /; Latin for 'shell'), also called a nasal turbinate or turbinal, [1] [2] is a long, narrow, curled shelf of bone that protrudes into the breathing passage of the nose in humans and various other animals.
Nasal meatus. In anatomy, the term nasal meatus [1] can refer to any of the three meatuses (passages) through the skull ' s nasal cavity: the superior meatus ( meatus nasi superior ), middle meatus ( meatus nasi medius ), and inferior meatus ( meatus nasi inferior ). The nasal meatuses are the spaces beneath each of the corresponding nasal conchae.
The nasal glands are the seromucous glands in the respiratory region of the nasal mucous membrane. [2] The three major types of nasal glands are anterior serous glands, seromucous glands, and Bowman glands. [3]
Anterior nares. Anterior nares are the external (or "proper") portion of the nose. The anterior nares open into the nasal cavity and allow the inhalation and exhalation of air. Each is an oval opening that measures about 1.5 cm anteroposteriorly and about 1 cm in diameter.