What kind of chemical does the mother fly deposit on egg?

The mother house fly deposits a glue-like chemical called "chorion" on the egg. This chorion hardens quickly after it is deposited and serves several important functions:

1) Protection: The chorion forms a protective layer around the egg, shielding it from mechanical damage, harsh environmental conditions, and potential predators.

2) Adhesion: The chorion helps the egg to adhere firmly to the chosen substrate. House flies typically lay their eggs on surfaces such as food, garbage, animal feces, or other organic matter. The chorion ensures that the eggs remain attached to these surfaces until they hatch.

3) Impermeability: The chorion is impermeable to water and gases. This prevents the egg from drying out and allows it to maintain a suitable internal environment for embryonic development.

4) Micropyle: The chorion contains a small opening called the micropyle. This opening allows the sperm to enter the egg during fertilization. After fertilization, the micropyle is plugged, sealing the egg and protecting the developing embryo.

The glue-like properties of the chorion ensure that house fly eggs can survive in diverse environments and develop successfully.