Activity

Egg structure study

Summary
Crack an egg, then draw the parts. Learn what they are each for.
Science content
Biology: Features, Adaptations of Living Things (K, 1, 3, 7)
Biology: Life Cycles (2)
Materials
  • egg
  • dark coloured dish to view in (shows the egg white better)
  • knife or hard edge to crack egg on
  • optional: worksheet for drawing egg
Procedure

Before cracking the egg, look at the shape of the egg, and show that as it rolls its shape makes it move in a circle. This means that eggs laid by birds do not roll off ledges.

Crack an egg at each table group.
Students draw the parts that they can see (maybe inside the outline of a shell, if the students are old enough to translate to the new shape).
Possibly use as an art project (see above water colour painting).

Students tell the class what they find, and together figure out/learn what the parts are for:
Yolk: Feeds the embryo. Protein, some fat, vitamins and minerals. (Iron, vit A, vit D, phosphorus, calcium, thiamine, and riboflavin.) Also lecithin, an effective emulsifier. Yellow like carrots.
Egg white: albumen, the Latin word for “white.” 40 different proteins. Layers of albumen protect the yolk and holds it in place. Also provides protein and nutrients for a growing embryo.
Chalazae: ropes of egg white. Hold the yolk in the center of the egg, so that the embryo can grow properly.
Eggshell: calcium carbonate. Air and moisture can pass through its pores. The shell also has a thin outermost coating called the bloom or cuticle that helps keep out bacteria and dust.
Membranes: between the eggshell and egg white. Defence against bacteria. Strong: made partly of keratin, a protein that’s also in human hair.
Air pocket: forms when the contents of the egg cool and contract after the egg is laid. (The small crater you see at the bottom of a hard-boiled egg is the imprint of the air cell.) Provide a pocket of oxygen for a growing chick.

More details on egg structure and function, as well as how these structures are nutritionally at https://www.saudereggs.com/blog/the-different-parts-of-an-egg/

Nicely detailed, but clear animation of a chick developing inside an egg: https://www.youtube.com/watch?v=PedajVADLGw&t=12s

Attached documents
Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5