This PSEB 7th Class Social Science Notes Chapter 1 Environment will help you in revision during exams.
PSEB 7th Class Social Science Notes Chapter 1 Environment
→ Earth: The earth is called a blue planet – 71% is water and 29% is an island.
→ Environment: Environment means surroundings. Its components are the Physical, Biological, and Cultural environment.
→ Physical Environment: The prevailing natural conditions comprising the land, water, and air.
→ Biological Environment: It consists of all life forms – animals including humans, plants, and other organisms.
→ Earth’s Spheres: The above four components form spheres called the lithosphere, hydrosphere, atmosphere, and biosphere.
→ Lithosphere: The outermost layer of the crust is called the lithosphere (Rock-sphere).
→ The rocky layer under continents is called Sial and under oceans is called Sima.
→ Hydrosphere: Rivers, lakes, seas, and oceans comprise this sphere and provide support to all life forms.
→ Atmosphere: The thin layer of air around earth.
→ Biosphere: Biosphere is a narrow zone of contact between land, water, and air. It is a life-giving sphere.
→ Biotic environment: The world of living things.
→ Abiotic environment: The world of non-living things.
→ Components of the environment: Land, Water, Air.
→ Crust: Hardtop layer of the earth.
→ Landforms: Mountains, Plateaus, Plains.
→ Ecosystem: A community of plants and animals within a particular physical environment.
→ Human Environment: Human life is closely related to the environment of the earth.