What can limit the spread of life on earth outside the biosphere?

The biosphere is the living shell of the earth. Only the hydrosphere, the watery shell of the planet, is fully inhabited by living organisms. Living organisms can be found even at the bottom of the Mariana Trench. Inside the hard shell – the lithosphere – the spread of living organisms is limited by the lack of oxygen and the temperature of the earth’s core. And the spread of life upward is limited by a lack of oxygen at high altitudes and by the action of ultraviolet radiation, therefore, living organisms are not found in the atmosphere above the ozone layer.