How does an Egg Yolk stay round?

An egg yolk doesn't actually stay perfectly round on its own. It's the shell of the egg that keeps it in that shape.

Here's why:

* The yolk is a liquid: Egg yolk is mostly made up of water, lipids, and proteins. It's a fluid, so without any container, it would just spread out.

* The chalaza holds the yolk: The chalaza, which are the two twisted strands of albumen (egg white) anchoring the yolk, help to keep the yolk centered within the egg. They act like little springs, pulling the yolk back to the center if it shifts.

* The shell provides structure: The hard, calcium carbonate shell of the egg gives it the shape and firmness that allows the yolk to maintain its roundness. It acts as a protective barrier and container for the yolk and white.

So, the egg yolk itself doesn't have any inherent ability to stay round, but it's the shell and the chalaza that work together to keep it in that shape.