Last Updated：2025/11/25
(anatomy) A membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals.
音声機能が動作しない場合はこちらをご確認ください
See correct answer
yolk sac
Edit Histories（0）
Source Word
yolk sac
（ plural ）
