Here's why:
* Different species: Cats and dogs are separate species, belonging to different families (Felidae and Canidae, respectively). This means they have significant genetic differences that make them incompatible for breeding.
* Chromosomal incompatibility: The number and structure of chromosomes differ between cats and dogs. Chromosomes contain genetic information, and they need to match up for successful fertilization and development.
* Reproductive incompatibility: Their reproductive systems are also different, making it impossible for them to mate and produce offspring.
While it's fun to imagine a "cat-dog" hybrid, it's simply not scientifically possible. There are some instances of animals from different species mating, but these are usually very closely related species.
It's great you're asking questions and being curious! There are lots of fascinating things to learn about the animal world.