One unique characteristic of a cat's tongue is its rough texture, which is due to tiny, backward-facing spines called papillae. These papillae are made of keratin, the same material as human fingernails. This rough texture serves several purposes for cats, including grooming, removing loose fur, and aiding in the consumption of meat by helping to strip it from bones. It's one of the many fascinating adaptations that make cats such efficient and specialized predators.