As you can see, there is more to an egg than meets the eye. Each part has its own job:
- Chalazae: the chords attached to either side of the yolk keep it the centre of the egg. It’s important because without them, the yolk would settle at the side and the chick could become malformed.
- Eggshell: there is a shell around the egg to protect it. Few people are aware that the eggshell is not airtight: it has about 10,000 tiny holes. We call these the pores, and they give the growing chick a sufficient air supply.
- Shell membrane: the membrane protects the contents of the egg against unwelcome visitors, such as bacteria.
- Thin egg white: the thin egg white is found between the shell membrane and the yolk.
- Thick egg white: the thick egg white is thick and cloudy and found around the yolk.
- Yolk: the yolk provides the chick with the food it needs.
- Blastodisc: this is where the egg will potentially be fertilised.
- Air space: this is where the chick draws its first breath before pecking through the shell