What are the two major group of animal kingdom?

The two major groups of animal kingdom, based on their body structure, are:

- Invertebrates: These are animals that do not have a backbone. They are the largest group of animals and include insects, spiders, worms, mollusks, and crustaceans.

- Vertebrates: These are animals that have a backbone. They include fish, amphibians, reptiles, birds, and mammals.