Components and Vocabulary of Chicken Eggs

These flashcards cover key vocabulary and structural facts about chicken eggs, including shell composition, membranes, albumen, yolk, chalazae, and related terminology.

What is the natural outer coating on an eggshell that seals its pores and helps keep out bacteria and dust?

The bloom (also called the cuticle).

What do we call the layer of material that covers an animal egg cell?

A membrane.

If a material is described as permeable, what does that mean?

It has pores or openings that allow liquids or gases to pass through.

Which two transparent protein layers found between the shell and egg white act as defenses against bacterial invasion?

The inner and outer membranes.

Which protein, also found in human hair, partially composes the egg's inner and outer membranes?

Keratin.

Approximately how many tiny pores can be found in a single eggshell?

As many as 17,000.

What substance makes up almost all of an eggshell’s structure?

Calcium carbonate (CaCO₃) crystals.

Why is an eggshell described as a semipermeable membrane?

Because air and moisture can pass through its pores.

From which Latin word is “albumen” derived, and what does that word mean?

From the Latin word “albus,” meaning “white.”

How many alternating layers of thick and thin albumen are found in an egg, and what do they mainly contain?

Four layers that together hold about 40 different proteins (plus water).

Compared with the white, how does the yolk differ in water and nutrient content?

The yolk has less water, more protein, some fat, and holds most of the egg’s vitamins and minerals.

List three vitamins or minerals present in an egg yolk.

Any three of the following: iron, vitamin A, vitamin D, phosphorus, calcium, thiamine, riboflavin.

Which compound present in the yolk makes it a good emulsifier?

Lecithin.

On what factors does the color of an egg yolk mainly depend?

The feed and breed of the hen.

What are the opaque, rope-like structures that anchor the yolk in the center of the egg called?

Chalazae.

What does a prominent chalaza indicate about an egg’s freshness?

The more prominent the chalazae, the fresher the egg.

What is the clear protein casing that surrounds the yolk and separates it from the albumen?

The vitelline membrane.

During which stage of egg formation is the vitelline membrane developed?

During the early stage in the chicken’s ovary.

What is the air-filled pocket found at the broad end of an egg called?

The air cell.