Earth is unique in the solar system for its ability to sustain life. It has liquid water and active geological processes. Earth's atmosphere protects it from solar radiation and maintains a climate suitable for organisms. About 70% of Earth's surface is covered by water, and it is the only known planet to have extensive quantities of liquid water on its surface. The presence of water, along with factors like temperature, nutrients, and a protective atmosphere, make Earth uniquely capable of supporting a wide diversity of life.

1. Earth and Life Science
Origin and
Structure
of the Earth
(Planet Earth)

2. Why is Earth
called “the
living planet?”

3. Earth is the only planet in the solar
system known to harbour life. Our
planet has a molten nickel-iron core
which gave rise to an extensive
magnetic field, which, along with the
atmosphere, shields us from harmful
radiation coming from the Sun. In this
module, you will understand why this
planet is called the “living planet.”

4. Just a part of the vast universe
is the solar system. From the
previous concepts learned,
identify the planets in the solar
system in the given illustration.

8. Earth is the only place in
the known universe
confirmed to host life and
is the only one known for
sure to have liquid water
in the surface.

9. Unique?
It has liquid water
Plate Tectonics
It has atmosphere that
shelters it from the worst of
the sun’s rays.

10. Why Earth is Unique?
Earth is the only planet in the solar system that
has a large amount of liquid water.
About 70% of the surface of the Earth is
covered by liquid or frozen water. Because of
this, Earth is sometimes called “blue planet.”
Planet Earth is habitable because it has the
right distance from the sun.

11. Why Earth is Unique?
It is kept warm by an insulating
atmosphere, and it has the right chemical
ingredients for life including water and
carbon.
It can provide water, oxygen, useful
biological products for human, and has
suitable weather and climate.

12. Earth
Venus
Mars

13. They have similarities

14. (1) They all are terrestrial planets,
made of solid rocks and silicates;
(2) They all have an atmosphere;
(3) They all almost have the same time
to rotate on their axes;

15. (4) Earth and Mars both have
water;
(5) They all have carbon
dioxide; and
(6) All have landforms.

17. (1) Venus has no water;
(2) Venus and Mars
don’t have oxygen; and
(3) Earth has life forms.

18. 1. Why is Earth called “the
living planet?”
A. It sustains life.
B. It has atmosphere
C. It has water at the surface
D. All of the above

19. 2. Which among the set of planets
are called terrestrial?
A. Jupiter, Neptune, Uranus
B. Mercury, Venus, Mars, Earth
C. Earth, Venus, Mars, Jupiter
D. Jupiter, Saturn, Uranus,
Neptune

20. 3. What makes the planet Earth
habitable compared to other
planets?
A. It has soil.
B.B. It has trees.
C.C. It has people.
D. It has liquid water.

21. 4. What makes planet Earth habitable?
A. It has comfortable distance from the
sun.
B. It has atmosphere that protects from
radiation.
C. The atmosphere holds carbon
dioxide and other gases.
D. All of the above

22. 5. Why is Earth called a terrestrial
planet?
A. It has life
B. It is closest to the sun
C. It is farther from the sun
D. It is placed at almost the middle
planets

23. 6. Which of the following best describes
the surface of the planet Earth?
A. a thick layer of hydrogen gas
B. cloudy and hot with lots of volcano
C. cold, rocky, and covered with red
dust
D. mostly water surface with some
areas of land

24. 7. Earth is said to be a unique
planet. Which answer verifies the
statement?
A. It supports life.
B. It is mostly covered in water.
C. Its atmosphere is mostly
nitrogen and oxygen.
D. All of the above

25. 8. Which is supported and
sustained by planet?
A. life
B. a moon
C. a rocky core
D. an atmosphere

26. 9. How many percent of
water comprises the
Earth?
A. 15% C. 50%
B. 30% D. 70%

27. 10. Which factors are needed
for organisms to live on Earth?
A. temperature and nutrient
B. atmosphere and energy
C. only A
D. both A and B

28. 11. What characteristics does the Earth
have to maintain an organism’s body to
survive?
A. Earth has a water cycle and atmosphere
B. Earth has volcanic activities to circulate
nutrients.
C. Earth has sub-surface water or molten
rock that can circulate and replenish
nutrients for organisms.
D. All of the above

29. 12. What makes Earth similar to Venus?
A. Earth and Venus are the right sizes to
hold a sufficient atmosphere.
B. Venus’ atmosphere is 100 times thicker
than Earth.
C. Among all the solid planets and moons,
only Earth, Venus, and Titan have
significant atmospheres.
D. Both A and C

30. 13. Which statement about the Earth will
help organisms to survive?
A. Earth has no protective equipment like
ozone.
B. Earth has layer water only for favorable
climate.
C. Earth has man-made natural cycles
D. Earth’s temperature is neither the hottest
nor the coldest among other planets.

31. 14. Which distinct characteristic made
Earth different from any other planet?
A. It is the only rocky planet.
B. It is the only planet that turns around in
space.
C. It is the only planet that has a large
amount of liquid water.
D. It is the only planet that changes its
structure

32. 15. What does Earth offers to
human in order to sustain life?
A. Earth has abundant plant life.
B. Earth has sufficient nutrients
from ocean to land.
C. Only A
D. Both A and B.