Question

Does the outer hard covering on a hen's egg is cell wall or is it something else? We can see plasma membrane in an egg but there's an additional covering which is hard, what is this?

Answer 1

Looking at the egg from the outside we see the shell, which is a hard, it is a protective covering made of calcium carbonate. The shell is porous. (There are about 7,000 pores in a chicken eggshell.) This allows the transfer of gases through the shell