Definitions for yolk sac

This page provides all possible meanings and translations of the word yolk sac

Random House Webster's College Dictionary

yolk′ sac`(n.)

  1. an extraembryonic membrane that encloses the yolk of eggs.

    Category: Developmental Biology

Origin of yolk sac:

1860–65

Princeton's WordNet

  1. yolk sac, vitelline sac, umbilical vesicle, vesicula umbilicus(noun)

    membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional

  2. yolk sac(noun)

    membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo

Wiktionary

  1. yolk sac(Noun)

    A membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals.

Freebase

  1. Yolk sac

    The yolk sac is a membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals. It functions as the developmental circulatory system of the human embryo, before internal circulation begins.

U.S. National Library of Medicine

  1. Yolk Sac

    The first of four extra-embryonic membranes to form during EMBRYOGENESIS. In REPTILES and BIRDS, it arises from endoderm and mesoderm to incorporate the EGG YOLK into the DIGESTIVE TRACT for nourishing the embryo. In placental MAMMALS, its nutritional function is vestigial; however, it is the source of INTESTINAL MUCOSA; BLOOD CELLS; and GERM CELLS. It is sometimes called the vitelline sac, which should not be confused with the VITELLINE MEMBRANE of the egg.

Translation

Find a translation for the yolk sac definition in other languages:

Select another language:

Discuss these yolk sac definitions with the community:


Citation

Use the citation below to add this definition to your bibliography:

Style:MLAChicagoAPA

"yolk sac." Definitions.net. STANDS4 LLC, 2014. Web. 28 Jul 2014. <http://www.definitions.net/definition/yolk sac>.

Are we missing a good definition for yolk sac?


The Web's Largest Resource for

Definitions & Translations


A Member Of The STANDS4 Network


Nearby & related entries:

Alternative searches for yolk sac: