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

alveolar sac

Etymology: L, alveolus, little hollow; Gk, sakkos
an air sac at one of the terminal cavities of lung tissue.

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] .

sac

(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