For quite some time I've been wondering about some of the things that make Antarctica and the Arctic similar, and what make them different. Well with some research, I got my answer.
Both Antarctica and the Arctic have birds, fish, krill, seals, and whales. Both places have research stations. They both have glaciers, icebergs, and snowstorms, and they are both among the regions of the Earth where precipitation is the lowest.
There are also quite a few differences between the Arctic and Antarctica, many of which I didn't know without research. I can't remember exactly where and when I found out this, but polar bears are found in the Arctic and not Antarctica. Penguins on the other hand are found in Antarctica but not the Arctic. Contrary to reality, polar bears and penguins can be found in the same habitat in some kid's stories, but then anything's possible in fiction.
If polar bears really could be found in Antarctica, and penguins really could be found in the Arctic, then polar bears would have a field day munching on those emperor penguins, since they aren't used to there being predators on land. They are also big and slow. A fully grown emperor penguin is only slightly smaller than a five year old human. When I was younger however, I did have visions in my head involving emperor penguins that were a head taller than humans, which of course doesn't happen in real life.
Bears evolved on the planet after Antarctica broke away from the other continents, so after that, there was no easy way of getting there. In the Arctic, there are caribou and beluga whales, while in Antarctica, there are Orcas and seals.
Antarctica and the South Pole are land areas covered in ice. On the other hand, the ice around the North Pole in the Arctic is pack ice and ice floes that float on the ocean, surrounded by land masses. Antarctica is much larger than the Arctic, and colder and windier as well. Since they are poles apart, on opposite sides of the planet, it is Summer in Antarctica when it is Winter in the Arctic, and vice-versa.
The Arctic has several land-based mammals, such as caribou (reindeer), muskox, and arctic foxes. Antarctica on the other hand doesn't have any mammals living on land – if you need somewhere to live, consider moving to Antarctica, to break the tradition :P
Antarctica only has a handful of plants, mosses, and lichens, while there are trees that grow in the Arctic. The Arctic has tundra where the vegetation is rich in Spring and Summer. While the Arctic has indigenous people and permanent residents, Antarctica has no permanent residents. Only researchers and others that visit but not live on the continent. Antarctica is an international territory, while all dry land in the Arctic is owned by some nation.