Fill in the answer at the end of the sentence. (You will not
have repeat answers for these questions).

1. This system of antimicrobial proteins will destroy foreign
invaders and system is effective against bacteria but not
viruses.
2. Molecules on the outside of the cell that allow the body to
recognize cells are self or foreign.

3. These structures return excess fluid from the tissues to the
bloodstream, and defend the body against specific invaders