Which layer of Earth's atmosphere is also home to the biosphere it is home to all living things?

Biosphere

Explanation:

The biosphere covers all living organisms on Earth. There is an estimated 20 million to 100 millions different species in the world organized into the 100 phyla that make up the five kingdoms of life forms. These organisms can be found in almost all parts of the geosphere.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.