Location of Air Cell in Chicken Egg

The air cell of a chicken egg is situated at the:

Correct Answer: Broad end of egg

The air cell is the space between the inner and outer shell membranes and is always located at the broad end of the chicken egg.

Why the Air Cell Is at the Broad End

• The broad end contains the maximum number of pores for gaseous exchange.
• After the egg is laid and cools down, the contents contract slightly, creating the air cell at the broad end.
• The embryo's head develops towards the broad end during incubation so it can use the air cell oxygen for the first breath before pipping.

Air Cell Size as a Quality Indicator

• Freshly laid egg: Air cell depth = 1–3 mm (very small).
• As the egg ages, the air cell enlarges due to evaporation of water and loss of CO₂.
• A large air cell = old egg.
• Air cell depth measured in specific gravity or brine flotation gives freshness index.

Why Other Options Are Wrong

• Narrow end → where the pointed end is; no air cell here.
• Middle → not anatomically possible; air cell is always at broad end.
• Side of egg → air cell location is fixed, not variable.