What are the functions of the labium?

It assists manipulation of the food during mastication. That would be their Mandibles, Pincers, mouth parts etc.. I believe the term labium is in reference to their reproductive system.

Yes you can determine the function of a function Key. You must access the registry and make the change.

Production of ribosomes-murdaman shy-

Here is an example for a variable, which is a function (function-pointer, actually): int (*myfun)(const char *s); myfun = puts; myfun ("Hello, world");