alveolar sac

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Related to alveolar sac: Alveolar ducts

al·ve·o·lar sac

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
Farlex Partner Medical Dictionary © Farlex 2012

al·ve·o·lar sac

(al-vē'ŏ-lăr sak)
Terminal dilation of the alveolar ducts that 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] .
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


(sak) [L. saccus, sack, bag]
A baglike part of an organ, a cavity or pouch, sometimes containing fluid. Synonym: saccus See: cyst

air sac

In a mammalian lung, an informal term for “pulmonary alveolus.”
See: alveolus.

allantoic sac

The expanded end of the allantois, well developed in birds and reptiles.

alveolar sac

Pulmonary alveolus.

amniotic sac

The inner fetal membrane that encloses the developing fetus and produces amniotic fluid.
See: chorion

chorionic sac

The outer fetal membrane that encloses the developing embryo.

conjunctival sac

The cavity, lined with conjunctiva, that lies between the eyelids and the anterior surface of the eye.

dental sac

The mesenchymal tissue surrounding a developing tooth.

endolymphatic sac

The expanded distal end of the endolymphatic duct.

heart sac

The pericardium.

hernial sac

In the peritoneum, a saclike protrusion containing a herniated organ.
See: hernia

Hilton's sac

See: Hilton, John

lacrimal sac

The upper dilated portion of the nasolacrimal duct situated in the groove of the lacrimal bone. The upper part is behind the internal tarsal ligament. It is 12 to 15 mm long.

lesser peritoneal sac

Omental bursa.

peritoneal sac

The enclosed, transparent mesothelial sac that is squeezed between the abdominal wall and the abdominal viscera.

vitelline sac

Yolk sac.

yolk sac

In mammals, the embryonic membrane that is the site of formation of the first red blood cells and the cells that will become oogonia or spermatogonia. Synonym: vitelline sac
See: embryo for illus
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
Pulmonary alveoli are composed of a myriad of alveolar sacs arranged in a fractal manner.
A more complex and physiologically realistic model was then developed that contained 45 alveolar sacs. Airflow and particle deposition in this model were compared to the simplified 4-alveoli (or 4-sac) model to determine the feasibility of using simplified alveolar models for inhalation dosimetry predictions and to evaluate the impact from gravitational orientation and inhalation depth.
To facilitate later reference to the four alveolar sacs, the upper alveolus was termed as Sac 1, the lower alveolus as Sac 4, and the left and right alveoli as Sac 2 and Sac 3, respectively (Figure 1(a), left panel).
To gain a better understanding of particle behaviors at different sizes, temporal variation of DFs was quantified in each section of the alveolar sacs (i.e., alveolar duct, four alveoli, and interalveolar pores, Figures 7(b)-7(d)).
The effects of gravity orientation angle on particle deposition in the alveolar sacs are shown in Figure 8.
Figure 9(b) shows the temporal and spatial variation of DFs in the alveolar sacs for breath-holding of 4 seconds.
When there was no septal wall, the alveolar sacs behave more like a single alveolus, as in Talaat and Xi [15], where particle deposition concentrated at the bottom of the alveolus (Figures 11(b) and 11(e)).
Another important finding in the present study is that histopathological analysis demonstrated significant reduction in the number of alveolar sacs and notably elevated crowded score in the lung parenchyma of hypoxia-treated animals compared to those in the sham controls.