Question

how is biosphere a dynamic and stable system

Answer 1

Biosphere is the life supporting zone of the earth where the atmosphere, the hydrosphere and lithosphere interact and make life. The interactions and interdependence among various biotic and physical components of the environment has caused the balance in nature. Thus, the biosphere is dynamic and stable

Answer 2

A constant interaction between biotic and abiotic components of biosphere makes it dynamic and stable.
Interaction consists of transfer of matter and energy between different components of biosphere.