Labrum - a cover which may be loosely referred to as the upper lip. Mandibles - hard, powerful cutting jaws. Maxillae - 'pincers' which are less powerful than the mandibles. They are used to steady and manipulate the food. Labium - the lower cover, often referred to as the lower lip.
The President, as head of the federal executive branch, is ultimately in charge of enforcing the immigration laws of the United States. In turn, he must make discretionary decisions about whether and when to prosecute immigration law violators through deportation and other sanctions.
Immigration Law: An Overview. Federal immigration law determines whether a person is an alien, the rights, duties, and obligations associated with being an alien in the United States, and how aliens gain residence or citizenship within the United States. It also provides the means by which certain aliens can become legally naturalized citizens with full rights of citizenship.