Grades K–2 · Organisms
How can a chick open its eggshell from inside?
Near the end of its growth inside an egg, a chick needs an opening to come out. The shell protected it while it grew, but the shell cannot stretch around the chick forever.
In the diagramA temporary hard tip helps open the shellenlarged beakegg tooth
The chick has a small hard bump near the tip of its beak called an egg tooth. By moving its head and body, it can press and chip against the shell and make a first break.
More movements can extend the cracks until the chick can push out. The egg tooth is temporary and is lost after hatching. It helps open the shell rather than chew the chick’s food.
About this explanation
Starting knowledge: Know that a chick grows inside an egg and that a hard shell can crack.
Sources
- Cooperative Extension Poultry — Avian Embryology