The Biosphere is the fourth sphere of the Earth – a life-supporting layer on the earth's surface that encompasses the Lithosphere, Hydrosphere and Atmosphere. Its vertical range is approximately 20 km, measured from the ocean floor to the troposphere. However, most plants and animals live in a very narrow section of about 1 km above and below the Mean Sea Level (MSL). The biosphere is made up of different ecosystems and biomes.
1. Basic Terms
| Term | Meaning |
|---|---|
| Species | All living things, large or small, are grouped into species |
| Habitat | The area in which an animal, plant or micro organism lives |
| Biodiversity | A wide variety of plants and animals living in a particular habitat |
| Ecology | The branch of science that deals about ecosystem |
| Ecologist | A person who studies ecology |