The document discusses the four subsystems of the Earth: atmosphere, biosphere, geosphere, and hydrosphere, detailing their characteristics and interconnected roles in the flow of matter and energy. It also describes the three layers of the Earth: the crust, mantle, and core, along with key discontinuities that define transitions between these layers. The text aims to educate students about these subsystems and layers, emphasizing the importance of stewardship and understanding Earth's systems.

1. The Subsystem and the layers
of the Earth
Earth and Life Science

2. OBJECTIVES:
At the end of the discussion, the students will
be able to:
• Determine the four subsystems of the Earth;
• Describe the characteristics of each subsystem;
• Identify the layers of the Earth;
• Differentiate the layers of the Earth; and
• Express one’s internalized role as steward of
the four subsystems concerning the flow of
matter and energy.

3. Earth is sometimes called the “water
planet” or the “blue planet” because seas
cover more than two-thirds of its
surface. Earth is the only planet in the
solar system with rain that falls from
clouds, runs over the land, and collects
in extensive oceans. It is also the only
body we know that supports life.

5. Subsystems of the Earth
The four subsystems of the Earth are:
1. Atmosphere – the gaseous layer above
the Earth’s surface primarily composed
of different gases such as nitrogen and
oxygen.
2. Biosphere – the zone of the Earth where
all forms of life exist. This serves as the
ecosystem of all living and non- living
organisms.

6. Subsystems of the Earth
The four subsystems of the Earth are:
3. 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.
4. Hydrosphere – the water part of the
Earth that includes oceans and glaciers.

7. For better understanding:
Atmosphere – it is the gaseous layer above the Earth’s
surface, primarily composed of 78% nitrogen and 21%
oxygen. Other gases like argon, carbon dioxide, carbon
monoxide, ozone, and other inert gases made the remaining
1%. The atmosphere supports life because animals and
oxygen, and plants need both carbon dioxide and oxygen. In
addition, the 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.

8. For better understanding:
Biosphere – the zone of Earth where all forms of life exist:
in the sea, on land, and in water. It is sometimes called as
the large ecosystem. This is the zone that life inhabits.
Biosphere is a very thin layer of the earth’s surface.
Geosphere – the solid Earth, consisting of the entire planet
from the center of the core to the outer crust. It includes
the core, mantle, and crust of the Earth

9. How does matter and energy flow across the four subsystems of the Earth?
The Earth consists of four subsystems, across whose
boundaries matter and energy flows, the atmosphere (air),
biosphere (living things), hydrosphere (water), and
geosphere (land). 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. It receives water from the
hydrosphere and a living medium from the geosphere.

10. Three Layers of the Earth
The crust is the thinnest and the outermost part of the
earth that consist of loose rocks and soil. It is mainly
composed of oxygen, silicon, iron, aluminum, sodium,
calcium, magnesium and potassium. It is also made up
of granite, sedimentary rocks and metamorphic rocks.
Just above the mantle and still part of the crust is the
Moho or Mohorovicic discontinuity. It is the
transitional boundary between the mantle and crust.

11. Three Layers of the Earth
Below the crust is the mantle. It is the thickest
layer of the earth that contains molten rock called
magma. It holds almost 80% of the earth's volume.
It is composed mainly of iron, oxygen, silicon,
magnesium and aluminum. The Gutenburg
discontinuity is the transitional boundary between
the lower mantle and to the next part of the earth
which is the core.

12. Three Layers of the Earth
The core is the center of the earth that is made up
mainly of iron and nickel. The core is divided into two,
outer core and inner core. The outer core is known to
be liquid because of the iron that in in liquid state.
Other components of the outer core are nickel, sulfur
and oxygen. The inner core is in solid state that
composed mainly of iron and nickel. The Lehman
discontinuity is the transitional boundary between the
outer core and inner core.

13. Three
Layers
of the
Earth

14. Three
Layers
of the
Earth

15. Five discontinuities inside the Earth
• Conrad Discontinuity
• Mohorovicic Discontinuity
• Repiti Discontinuity
• Gutenberg Discontinuity
• Lehman Discontinuity

16. Mohorovicic Discontinuity
The transition zone between the crust and mantle is
called as mohorovicic discontinuity. The
mohorovicic discontinuity was discovered by
Andrija Mohorovicic in the year of 1909. The Moho
lies at the depth of 35km beneath the continents and
8km beneath the oceanic crust. The Moho separates
both the continental crust and the oceanic crust from
underlying mantle.

17. Gutenberg Discontinuity
The mantle –core transition zone is called
Gutenberg discontinuity. In the year of 1912
Weichert Gutenberg was discovered this
discontinuity at the depth of 2900km beneath the
earth surface. In this zone the velocity of seismic
waves changes suddenly.

18. Gutenberg Discontinuity
It is the transition zone between outer and inner
core. Discovered by seismologist Inge
Lehmann.It appears beneath continents, but not
usually beneath oceans, and does not readily
appear in globally averaged studies.