[M2] Origin and Structure of the Earth (The Subsystem)

• The four subsystems of the Earth are: Atmosphere, Biosphere, Geosphere, Hydrosphere
• Atmosphere – the gaseous layer above the Earth’s surface primarily composed of different gases such as nitrogen and oxygen.
• Biosphere – the zone of the Earth where all forms of life exist. This serves as the ecosystem of all living and non- living organisms.
• Geosphere – the solid part of the Earth that consists the entire planet from the center of the core to the outer crust. It includes core, mantle, and crust of the Earth.
• Hydrosphere – the water part of the Earth that includes oceans and glaciers.
• . Atmosphere – it is the gaseous layer above the Earth’s surface, primarily composed of 78% nitrogen and 21% oxygen
• The atmosphere supports life because animals and oxygen, and plants need both carbon dioxide and oxygen.
• Atmosphere supports life indirectly by regulating climate
• Air acts as both a blanket and a filter, retaining heat at night and shielding from direct solar radiation during the day
• Biosphere – the zone of Earth where all forms of life exist: in the sea, on land, and in water.
• Biosphere - sometimes called as the large ecosystem
• Biosphere is a very thin layer of the earth’s surface
• Biosphere is the zone that life inhabits.
• Geosphere – the solid Earth, consisting of the entire planet from the center of the core to the outer crust.
• Geosphere includes the core, mantle, and crust of the Earth.
• Hydrosphere – the water part of the Earth which circulates among oceans, continents, glaciers, and atmosphere.
• Oceans cover 71% of the Earth and contain 97.5% of its water.
• Energy flows through the atmosphere mostly by convection
• The atmosphere provides the geosphere with heat and energy needed for rock breakdown and erosion.
• The biosphere receives gases, heat, and sunlight (energy) from the atmosphere.
• The atmosphere receives water from the hydrosphere and a living medium from the geosphere.
• Convection is the movement of particles through a substance, transporting their heat energy from hotter areas to cooler areas.