Question

The term biosphere is used for the zone of Earth , where life exists
A)On the lithosphere
B)In the hydrosphere
C)In the lithosphere and hydrosphere
D)In the lithosphere,hydrosphere and atmosphere

Answer 1

The biosphere is made up of the parts where life occurs on Earth. The biosphere stretches to the dark world of ocean trenches, to green rain forests and high mountain tops from the deepest root systems of trees.

Complete answer:
The Earth is defined by scientists in terms of spheres. The Earth's dense surface layer is the lithosphere. The atmosphere is the air layer which extends above the lithosphere. The Earth's water makes up the hydrosphere on the surface, in the soil, and in the air.

The biosphere overlaps all these spheres since life occurs on the earth, in the air, and in water. While the biosphere is about 20 kilometres (12 miles) from top to bottom, from about 500 metres (1,640 feet) below the surface of the ocean to about 6 kilometres (3.75 miles) above sea level, almost all life exists.

For about 3.5 billion years, the biosphere has existed. The earliest life-forms in the biosphere, called prokaryotes, survived without oxygen. Ancient prokaryotes contained species such as bacteria and archaea that were single-celled.

A special chemical process has been produced by some prokaryotes. They were able to use sunlight to create simple sugars and oxygen, a process called photosynthesis, out of water and carbon dioxide. These photosynthetic species were so abundant that the biosphere was altered. The atmosphere has produced a combination of oxygen and other gases over a long period of time that could support new ways of life.

The addition of oxygen to the biosphere has facilitated the creation of more complex life-forms. Millions have evolved from various plants and other photosynthetic organisms.
Both areas populated by living things are included in the biosphere, such as the hydrosphere that includes all the water; the atmosphere that includes all the air; and the lithosphere that includes all the soil.

Hence, the correct answer is option (D)

Note: Animals that eat plants (and other animals) have evolved. Bacteria and other species have evolved to decompose dead animals and plants or to break them down. The biosphere is benefiting from this web of food.