Final answer:
Diagonal is not a recognized welding position; overhead, vertical, and horizontal are. In anatomy, the midsagittal plane divides an animal into equal right and left portions.
Step-by-step explanation:
The welding position that is not recognized among the options provided is diagonal. Recognized welding positions include overhead, vertical, and horizontal. These terms are used to describe the position of the welder in relation to the workpiece being welded. On the other hand, when discussing anatomy and the plane that divides an animal into equal right and left portions, the correct term is midsagittal. The midsagittal plane, also known as the median plane, bisects the body vertically through the midline, creating two symmetrical halves.