Living organisms have bodies with some identified organs (a unit that performs some useful function). The organisms have their own shapes and structures.
Many organisms have similar kinds of organs and shapes. Those organs belonging to one category have same shape, same function, composed of same cells and behave in similar way. The structure (interconnections of the organ with other organs) and role of that organ in the body are similar to other organisms in the species. Basically, organ systems are similar in one species.
Body design means the various parts in the body, the way they are interconnected, and their physical shapes.