How does a birds egg protect and nourish a developing embryo compared to a frogs egg?

A bird's egg is designed with a hard shell that provides physical protection and a complex structure that includes membranes and a nutrient-rich yolk to nourish the developing embryo. The albumen (egg white) also offers additional protection and hydration. In contrast, a frog's egg is typically soft and jelly-like, lacking a hard shell, which allows for more immediate environmental interaction but provides less protection. The jelly serves to protect the eggs from predators and desiccation, while the surrounding water provides nutrients and a suitable environment for development.