5
5.. . The ocean floor 66.. features include mid-oceanic
7
7.. , oceanic trenches and 88.. plains. Submarine 99..
may create volcanic archipelagos.
T
Trruuee oorr FFaallssee?? WWrriittee T oorr F.. 1
1.. The Earth is the only planet with an atmosphere which contains oxygen. 2
2.. Hydrogen is the most abundant gas in the Earth’s atmosphere. 3
3.. The average temperature on the Earth’s surface is 18 ºC. 4
4.. The gravitational attraction of the Moon produces ocean tides. 5
5.. Earthquakes and volcanoes are the result of geological activity.
3 3 2 2
relief volcanoes living things abyssal land relief ranges shelves ridges continental
6 6.. 7 7.. 8 8.. 4 4.. 3 3.. 2 2.. 1 1.. 5 5..
mountain range
877310 _ 0028-0035.qxd 4/8/08 14:24 Página 31PLANET EARTH
WORKSHEET 3
2
NAME: CLASS: DATE:
C
Coommpplleettee tthhiiss ttaabbllee wwiitthh tthhee mmiissssiinngg iinnffoorrmmaattiioonn aabboouutt tthhee ffoouurr ‘‘sspphheerreess’’ ooff tthhee EEaarrtthh..
1 1
_ _____ // 2200 D
Doo yyoouu rreemmeemmbbeerr?? UUssee tthheessee jjuummbblleedd uupp nnuummbbeerrss ttoo ccoommpplleettee tthhee tthhrreeee FFaaccttss FFiilleess..
2 2
2,900 km
from 7 to 70 km 4,500 m11,034 m
21%
from 7 to 10 kmover 4,000ºC
78%3
2,500 15ºC F FAACCTTSS FFIILLEESS T Thhee ggeeoosspphheerree aa.. - the thickness of the continental crust
b
b.. - the thickness of the oceanic crust
c
c.. - the distance the mantle lies below the crust
d
d.. the temperature of the cores
T
Thhee hhyyddrroosspphheerree a
a.. - the number of years ago that Thales described the water cycle
b
b.. - the number of states in which water exists
c
c.. - the average depth of the ocean
d
d.. - the depth of the Mariana trench
T
Thhee aattmmoosspphheerree a
a.. - the percentage of nitrogen in the air
b
b.. - the percentage of oxygen in the air
c
c.. - the average temperature on the Earth’s surface.
S
Spphheerree IIss mmaaddee uupp ooff CCoonnttaaiinnss G
Geeoosspphheerree three concentric layers
nitrogen, oxygen and carbon dioxide
H
Hyyddrroosspphheerree liquid water, snow and ice
land and water
33
쮿 EESSSSEENNTTIIAALL NNAATTUURRAALL SSCCIIEENNCCEE 11쮿 PHOTOCOPIABLE MATERIAL © 2008 Richmond Publishing / Santillana Educación, S.L. 쮿
PLANET EARTH
WORKSHEET 4
2
NAME: CLASS: DATE:
S
Seenntteennccee lloooopp.. WWoorrkk iinn ppaaiirrss.. TTaakkee ttuurrnnss ttoo ssttaarrtt oorr ffiinniisshh tthhee sseenntteenncceess..
1
1.. The Earth revolves … 2
2.. The Earth rotates … 3
3.. The Moon revolves … 4
4.. Solar eclipses occur … 5
5.. Lunar eclipses occur … 6
6.. The orbit of the Earth … 7
7.. The full Moon occurs … 8
8.. The new Moon occurs … 9
9.. The Moon orbits the Earth … 1
100.. The axis of the Earth … 1
111.. At any time, one half of the Earth … 1
122.. When a hemisphere is tilted towards the Sun, …
a
a.. … when the Earth is between the Sun and the Moon. b
b.. … when the Earth blocks sunlight from the Moon. c
c.. … is facing the Sun. d
d.. … on its own axis. e
e.. … when the Moon blocks sunlight from the Earth. ff.. .… it is summer.
g
g.. … in approximately 29.5 days. h
h.. … an elongated circle called an ellipse. ii.. … around the Earth.
jj.. … around the Sun. k
k.. … when the Moon is between the Sun and the Earth. ll.. … is slightly tilted. 1 1 _ _____ // 2244 877310 _ 0028-0035.qxd 4/8/08 14:24 Página 33
PLANET EARTH
WORKSHEET 5
2
NAME: CLASS: DATE:
F
Frroomm tthhee iinnffoorrmmaattiioonn iinn tthhee tteexxtt,, wwhhiicchh ppllaanneett iiss ccoonnssiiddeerreedd ttoo bbee EEaarrtthh’’ss ttwwiinn??
C
Coorrrreecctt tthhee iinnffoorrmmaattiioonn iinn tthhee ffoolllloowwiinngg sseenntteenncceess.. 1
1.. The clouds on Earth contain sulphuric acid.
2
2.. The Earth is smaller than this planet.
3
3.. At the beginning, this planet was desert-like.
4
4.. Then water appeared on it.
5
5.. This planet is named after the Roman god of war.
6
6.. Mountains form most of the surface of this planet.
2 2 1 1 _ _____ // 1155 Does Earth have a twin?
There is a planet in the Solar System which is completely covered in thick clouds. It has a volcanic surface and a poisonous atmosphere. Its average temperature is 480 ºC, while on Earth the average
temperature is 15 ºC. Its clouds contain sulphuric acid rather than water. It cannot possibly support life! Yet for years scientists have considered this planet as Earth’s twin.
Why?
Firstly, it is similar in size and mass to Earth. Both planets are very close to each other, much closer than any other pair of planets. Both are quite young
geologically. (They have very few craters caused by meteorite impacts on their surfaces). In the beginning, the Earth’s twin probably had oceans. Then, the oceans
turned into desert land as the water disappeared. This was due to the accumulation of carbon dioxide in its atmosphere. (On Earth, this is known as the greenhouse effect!)
Finally this planet, named after the Roman goddess of love and beauty, has a variety of geographical features similar to those on Earth. These include plains (about 65 % of the surface), mountains, canyons, and valleys.
If this is enough to consider the mysterious planet ‘Earth’s twin’, imagine how incredibly different all the other planets must be from ours!
35
쮿 EESSSSEENNTTIIAALL NNAATTUURRAALL SSCCIIEENNCCEE 11쮿 PHOTOCOPIABLE MATERIAL © 2008 Richmond Publishing / Santillana Educación, S.L. 쮿
PLANET EARTH
TEST 2
2
NAME: CLASS: DATE:
C
Ciirrccllee tthhee ccoorrrreecctt aannsswweerr.. 1
1.. The Earth’s magnetic field protects living beings from
(a) carbon dioxide (b) solar radiations (c) earthquakes.
2
2.. In summer, the Sun’s rays strike the Earth’s surface
(a) perpendicularly (b) at an oblique angle (c) at an angle of 135º.
3
3.. Seasons occur at different times of the year in the Northern and Southern Hemispheres because of
(a) the revolutions of the Earth (b) the rotation of the Earth (c) the tilt of the Earth’s axis.
4
4.. The Moon rotates it orbits the Earth.
(a) at the same speed as (b) faster than (c) more slowly than
5
5.. As a result,
(a) the same side of the Moon always faces the Earth (b) tides occur (c) eclipses occur.
6
6.. A lunar month lasts a lunar day.
(a) as long as (b) longer than (c) less than
7
7.. When the Moon passes between the Sun and the Earth and blocks off the sunlight, it is called
(a) a solstice (b) a solar eclipse (c) a lunar eclipse.
8
8.. A lunar eclipse can only take place during the
(a) new Moon (b) first or last quarter (c) full Moon.
9
9.. The shadow projected by the Earth on the Moon during an eclipse is called the
(a) penumbra (b) umbra (c) nebula.
1
100.. During the first quarter of its phase, the Moon
(a) rises at noon and sets at midnight (b) rises and sets with the Sun (c) rises at midnight and sets at noon.
R
Reeaadd tthhiiss ppaassssaaggee aanndd ffiillll iinn tthhee ggaappss..
2 2 1 1 _ _____ // 1155 The Earth
Some specific characteristics make the Earth a unique planet in the Solar System.
In the first place, it has an atmosphere containing 11.. which is essential for plant and animal respiration. The Earth’s atmosphere also contains carbon dioxide which is essential for 22.. . It also has a 33.. cycle and an average temperature of 44.. . The Earth’s 55.. field protects living beings from dangerous solar radiations. For all of these reasons, the necessary conditions for life exist on our planet.