yolk sac

常见例句

The yolk sac and yolk stalk on one of them were well preserved.
觀察了三例人胚外形，其中一例還有保存良好的卵黃囊和卵黃蒂。
The results showed that more than80%of nutrition in yolk sac were utilized in59hours, which suggested that it was the main period of yolk sac utilization.
結果表明，在59時齡以內80%以上的卵黃囊營養被吸收利用，說明這一時期是卵黃囊吸收利用的主要時期。
I do not believe, however, that this is normal, since in the wild, young with such a large yolk sac probably would not survive without parental protection.
我不相信，不過，這是正常的，因爲在野生環境年紀這麽大的卵黃囊，也許就不會生存父母的保護。