Question

Why does life exist only on earth?

Answer 1

Earth:

1. Earth is the third planet in the ecosystem.
2. It is called the blue planet as 70% of its surface is covered with water and only 30% is occupied by land.
3. Earth possesses different spheres such as atmosphere, lithosphere, hydrosphere, and biosphere.
4. The biosphere is the region where all life is possible.
5. It comprises of living and nonliving elements that interact together establishing a community called an ecosystem.
6. The atmosphere has different gases out of which 78% is nitrogen, 21% is oxygen, and the rest is occupied by gases such as carbon dioxide, argon, etc.
7. These gases play a vital role in the survival of organisms.
8. The water from the hydrosphere and land from the lithosphere is also equally important for organisms existing in the biosphere.

Existence of life on Earth:

1. The distance of Earth from the sun is adequately allowing the earth to be perfectly hot and cold during different seasons for the survival of organisms.
2. The atmospheric conditions have changed over due course of time, bringing the temperature of Earth down which favors the existence of life.
3. The existence of the biosphere makes the availability of different resources like food, water, and air.
4. Earth is covered by the UV protective layer called ozone which protects the organisms from harmful ultraviolet radiations (UV).

The above-mentioned reasons make the Earth a suitable place for the existence of life.