Vertebrate animals have backbones and internal skeletons, including fish with scales, amphibians with moist skin and no scales, mammals with fur or hair, birds with feathers, and reptiles with scales. Invertebrate animals lack backbones and internal bones, with insects making up the largest group of invertebrates.

1. Vertebrate & Invertebrate Animals

6. Birds : feathers

7. Reptiles : scales

10. Insects are the largest group of invertebrates

11. Parts of an insect