(I assume this question was asked as a matter of personal interest. If not, I concur with the recommendation to speak to a patent lawyer rather than acting on anything written below.)
There are three types of patents: utility patents, design patents, and plant patents.
I don’t know much about plant patents other than that you have to asexually reproduce a distinct type of plant. The distinction is both genetic and physical, but the correlation between genotype and phenotype in plants is such that the question probably doesn’t apply. You cannot patent an aberration, so a physically distinct instance of the same plant would just be an outlier.
Design patents are specified in terms of physical qualities, so anything physically dissimilar would necessarily fall outside the scope of the original patent. There is, however, a determination to be made by a court regarding how similar a physically dissimilar thing can be without violating the original patent.
Utility patents apply to processes, machines, manufactured objects, and synthesized compounds. A synthesized compound—called a “composition of matter” in the patent laws—is physically defined. It could be a chemical compound or a created microorganism, but in either case the physical features will be quite constant. Manufactured objects and machines are subject to similar rules as design patents. There are a lot of ways to make a hammer, and it is up to the courts to determine when something is so dissimilar as to no longer count (not that hammers are themselves actually patented by anyone). Processes, meanwhile, are specific methods for achieving some end. While there may be many ways to initiate a process, the basic process underlying everything is what matters.
The wording of a patent, however, is less important than some people think. A design patent contains a copy of the design. A utility patent for a machine contains specifications. These pictures are worth a thousand words, as the saying goes. In the case of the zipper, for instance, it is the device itself that is patented. Using a zipper on non-clothing items such as luggage still violates the patent because the description is not the only part of the patent. As noted by @flutherother, however, the wording can help guide the courts when making a determination of similarity or prior art. So while the wording may not be dispositive, it is still very important.