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單詞乎

yolk sac

yolk sac是什么意思、yolk sac怎么讀

yolk sac漢語(yǔ)翻譯

卵黃囊
【醫(yī)】 卵黃囊

yolk sac英語(yǔ)解釋

名詞 yolk sac:

  1. membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional
    同義詞:vitelline sac, umbilical vesicle, vesicula umbilicus
  2. membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo
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