Survival of the fetus outside the mother is not possible until at least _____ weeks after fertilization, a time referred to as the edge of viability. At this point, major _____ will be required, and lifelong _____ may result even if the child survives.

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.