Earth's Structure and Life Systems

Composed of different layers and interconnected subsystems.
Supports a wide range of life forms, from simple organisms to humans.
Earth is uniquely capable of sustaining life compared to other planets in the solar system.

All parts of Earth continuously interact, creating a complex system.
Subsystems of Earth's system include the lithosphere, atmosphere, hydrosphere, and biosphere.

Represents the solid components of Earth.
Composed of tectonic plates that shift over time.
Not a continuous layer; divided into many plates that move relatively, drifting at about 12 cm per year.
Pangaea, a supercontinent proposed by Alfred Wegener, illustrates past plate arrangements.
Currently recognized as having more than 50 tectonic plates, including the Philippine Sea Plate.

A thin layer of gases that envelops the lithosphere.
Derived from Greek; "atmos" means gas and "sphaira" means globe or ball.
Comprises multiple layers: troposphere, stratosphere, mesosphere, thermosphere, and exosphere.

Troposphere:
- Extends up to 14.5 km, where weather phenomena occur.
Stratosphere:
- Ranges from 14.5 km to 50 km and contains the ozone layer, which protects against UV radiation.
Mesosphere:
- Extends from 50 km to 85 km; protects Earth from space debris.
Thermosphere:
- Ranges from 85 km to 600 km; contains charged particles affected by the Earth's magnetic field, creating auroras.
Exosphere:
- The outermost layer, extending up to 10,000 km.

Encompasses all water on Earth, in vapor, liquid, and ice forms.
Comprises 97.5% saltwater and 2.5% freshwater.
Includes oceans, lakes, rivers, and clouds; plays a critical role in the water cycle.

Comprises all living organisms, including microbes, plants, and animals.
Extends from the upper atmosphere to the depths of oceans.
Vital for maintaining life on Earth as matter and energy circulate among different subsystems.

Matter and energy cycle through subsystems, essential for life.
Specific cycles include:
- Nitrogen Cycle: Essential for life, involving nitrogen fixation and decomposition.
- Carbon Dioxide-Oxygen Cycle: Involves photosynthesis and respiration to balance oxygen and carbon dioxide levels.
- Water Cycle: Describes the movement of water through evaporation, condensation, and precipitation.

Life on Earth heavily relies on the dynamic interactions and cycles among lithosphere, atmosphere, hydrosphere, and biosphere, deeply illustrating the interconnectedness of Earth's systems.