Do all animals.....?

Even the cells within a single animal don't all look the same. For example, you've got muscle cells that are markedly different from skin cells, and kidney cells that bear little resemblance to neurons. The same thing happens in plants; plant and animal cells can become highly specialized to perform a certain type of task. Therefore, when you ask a question like this one, you have to be more specific. For example, you could say: "Do the muscle cells of a lion look the same as the muscle cells of a giraffe?" To that question I would say, probably not. Each animals cells (be they muscle, nerve, kidney, blood, or heart cells) are suited to the survival of that animal. Since a giraffe will have different survival needs than a lion, you would most likely be able to tell a difference between the two. I'm not saying you could just look at two pictures, one of a lion's muscle and one of a giraffe's, and instinctively identify each one, but if you were told what the pictures were, you might be able to distinguish between them.