When lymphatic trunks merge, they form the largest lymphatic vessels in the body, the _____. (There are only _____ of these in the body; in some individuals, the _____ one is absent and several trunks drain into the venous system directly.)

3000+ review questions on anatomy and physiology. 

Anatomy refers to the internal and external structures of the body and their physical relationships, whereas physiology refers to the study of the functions of those structures.