This almost sounds like a trick question; if you are a citizen you can't be in the US illegally, and if you're in the US illegally you could not be a citizen!
That being said, if a person is residing in the US without a valid visa or residency permit, they would be classified as an illegal alien or the more politically correct term, "undocumented immigrant".
Naturalization
Naturalization
alien
Naturalization
aerobic respiration
phenotype
phenotype
phenotype
Anaerobic
Moonshine is a term used to describe alcohol that was made illegally. Beer brands include Molson, Michelob and Miller.
metabolism
It is Alive! Cytoplasm is what is found in the interior of all Living Cells - the term protoplasm is used to describe the first cytoplasmic mixture.