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Related to air sac: bronchiole
1. terminal dilation of the alveolar ducts, which give rise to alveoli in the lung; a small air chamber in the pulmonary tissue from which the pulmonary alveoli project like bays and into which an alveolar duct opens; Synonym(s): sacculus alveolaris [TA]
2. in birds, air-containing extensions of bronchi that connect with bone cavities.
Synonym(s): air sac
1. An air-filled space in the body of a bird that forms a connection between the lungs and bone cavities and aids in breathing and temperature regulation.
2. See alveolus.
3. A saclike, thin-walled enlargement in the trachea of an insect.
4. An inflatable pouch attached to the larynx in certain mammals, including the nonhuman great apes.
a small, terminal cavity in the lung, consisting of the alveoli connected to one terminal bronchiole.
air saca thin-walled extension to the lungs, present in the thorax, abdomen and bones of birds. Air sacs also occur as diverticula (outgrowths) of the TRACHEA in insects, where, as in birds, they are important in respiration.
a pouch; a baglike organ or structure. See also conjunctival sac.
1. alveolar sac.
2. one of the large air-filled diverticula of the respiratory system of birds. See also air sacs.
the spaces into which the alveolar ducts open distally, and with which the alveoli communicate.
see anal sacs.
the blind, flattened cerebral end of the endolymphatic duct.
the peritoneal pouch that encloses a herniated viscus or mesentery.
see lacrimal sac.
see anal sacs.
the pleura-lined cavity which contains the lung.
one of the dorsal and ventral sacs of the rumen which are themselves further subdivided to create a caudodorsal sac and a caudoventral sac.
the extraembryonic membrane connected with the midgut; in vertebrates other than true mammals, it contains a yolk mass. See also yolk sac.