Flatworms, also known as Platyhelminthes, constitute a phylum of about 20,000 species of rather uncomplicated invertebrates characterized by their soft bodies and lack of segmentation. They differ ... Biology is the story of life on earth.

Understanding the Context

Biology is the story of evolution of living organisms on earth. All living organisms – present, past and future, are linked to one another by the sharing of the common genetic material, but to varying degrees. Chapter 02 of Biology ncert book titled - Biological classification for class 11 Biology is the study of living organisms. The detailed description of their form and appearance only brought out their diversity.

Key Insights

It is the cell theory that emphasised the unity underlying this diversity of forms, i.e., the cellular organisation of all life forms. A description of cell structure and cell growth by division is given in the chapters comprising this unit. Cell theory also created ... Chapter 18 of Biology ncert book titled - Body fluids and circulation for class 11 SUMMARY As a branch of biology, Ecology is the study of the relationships of living organisms with the abiotic (physico-chemical factors) and biotic components (other species) of their environment. It is concerned with four levels of biological organisation-organisms, populations, communities and biomes.

Final Thoughts

Chapter 07 of Biology ncert book titled - Structural organisation in animals for class 11 Chapter 20 of Biology ncert book titled - Locomotion and movement for class 11 MSN: Flatworms defy stem cell rules, offering a blueprint for human regeneration A team of scientists has mapped the regions surrounding stem cells in planarians—small flatworms that are famous for being able to regrow whole bodies from small fragments—and discovered something ...