yolk sac

常见例句

The yolk sac and yolk stalk on one of them were well preserved.
观察了三例人胚外形，其中一例还有保存良好的卵黄囊和卵黄蒂。
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.
结果表明，在59时龄以内80%以上的卵黄囊营养被吸收利用，说明这一时期是卵黄囊吸收利用的主要时期。
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，不过，这是正常的，因为在野生环境年纪这么大的卵黄囊，也许就不会生存父母的保护。