

In the NCERT Biology book “Biology” (Class 11), Chapter — “Structural Organisation in Animals”, you explore how animal bodies are organized from tissues to complex organ systems. You learn about the four main types of animal tissues and how they function together.
Through detailed study of earthworm, cockroach, and frog, you understand the structural differences between invertebrates and vertebrates. You examine various organ systems and observe how they coordinate to maintain life processes.
This chapter strengthens your observational and diagram-based learning skills while helping you connect anatomical structures with their biological functions.