Any animal that hatches from a shell comes from an embryo. Actually any animal at all comes from an embryo. But the most common animal you would think of would be a chick.
platypus and spinney anteater
It is to protect the embryo inside the egg.
nothing
It gives the embryo oxygen it needs to survive in the egg.
because i don't no ignore that person, it is called a cotyledon :]
The developing embryo takes its nourishment from the yolk inside the egg. The embryo doesn't need air until it is ready to break out of its shell.
Inside a fertilized egg that will hatch, you'll find a developing embryo surrounded by a yolk, which provides nutrients. The embryo is typically visible as a small, dark spot on the surface of the yolk, enclosed by a clear, jelly-like albumen (egg white). As the development progresses, the embryo grows and structures, such as blood vessels and membranes, become more defined. The egg's shell remains intact until the embryo is fully developed and ready to hatch.
The bird embryo develops inside the protective shell of the egg, using the egg yolk as a source of energy and materials from which it will develop.
To protect the embryo inside it until it is fully grown and can hatch its own way out der
Seeds have a shell to protect the embryo inside from physical damage, dehydration, and predators. The shell acts as a barrier, helping the seed to stay dormant until conditions are favorable for germination.
The embryo of a chicken egg is right below the shell.
Most reptiles simply abandon their eggs to 'fate' once they're laid. Some species of lizards and snakes will stay close-by and actively discourage anything from disturbing the 'nest'. The majority of animals know instinctively to avoid contact with reptiles.