The type of egg produced by reptiles, birds, and prototherian (egg-laying) mammals (amniotes), in which the embryo develops inside an amnion. The shell of the egg is either calcium-based or leathery.
科学参考收录了60776条科技类词条,基本涵盖了常见科技类参考文献及英语词汇的翻译,是科学学习和研究的有利工具。