ConclusionMars is about the same size as Earth. And it is fairly close to the Sun. But Mars is cold. Mars also doesn't have a very big atmosphere to protect life from ultraviolet rays which can destroy life. So, it really seems like there may not be any life on Mars.
But, there are life forms on Earth which can survive in very harsh environments. If life ever does exist on Mars, maybe it will look very different than the life that we know of! What do you think life on Mars would look like?