Libro de texto_Natural Science 1 ESO

NATURAL SCIENCE Projecte de Seccions Europees Illes Balears

1ยบ ESO EMMA Sร NCHEZ CLARK

© 2014 EDICIONS TALAIOTS, S.L. Se reservan todos los derechos.

Ninguna parte de esta publicación puede ser reproducida, almacenada o transmitida por ningún medio sin el permiso del autor

Edita: EDICIONS TALAIOTS, S.L. C/. Castelló de la Plana, 30 07181 Palmanova (Calvià) Tel. 971 75 16 04 Impresión y maquetación: INSTITUT - Impremta Digital (Palma) Autor: Emma Sánchez Clark ISBN: 978-84-15672-20-3 Depósito Legal: DL-PM-924-2014

CONTENTS

UNIT 1: EXPLORING THE UNIVERSE

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UNIT 2: OUR PLANET THE EARTH

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UNIT 3: MATTER

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UNIT 4: PURE SUBSTANCES AND MIXTURES

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UNIT 5: LIVING THINGS

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UNIT 6: THE DIVERSITY OF LIFE

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UNIT 7: THE PLANT KINGDOM

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UNIT 8: THE ANIMAL KINGDOM

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UNIT 9: ROCKS AND MINERALS

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UNIT 10: THE ATMOSPHERE

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UNIT 11: THE HYDROSPHERE

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UNIT 1. EXPLORING THE UNIVERSE CONTENTS 1.

The universe, stars and galaxies

2.

Theories about the structure of the universe

3.

The Solar System

4.

Glossary

5.

Activities

1. THE UNIVERSE, STARS AND GALAXIES The universe contains galaxies.

A galaxy is a group of billions of stars.

Our galaxy is called the Milky Way and it has a spiral shape.

The universe is very old. It originated 14 billion years ago after a large explosion (Big Bang).

Stars look like small points of light but they are big. They look small because they are very far away from us.

Stars are big balls of hot gas. Inside stars nuclear fusion reactions take place which produce light and heat.

Stars have different colours, the hottest are blue and the least hot are red. Yellow stars have a temperature between the blue and red stars. The Sun is a yellow star.

Stars have different sizes, for instance, the Sun is a medium size star.

2. THEORIES ABOUT THE STRUCTURE OF THE UNIVERSE

Geocentric theory: The Earth is at the centre of the universe and the rest of heavenly bodies orbit it. It was developed by the Greeks thousands of years ago.

Theories about the structure of the universe

Heliocentric theory: The Sun is at the centre of the universe and all the planets orbit it. This theory w as developed by Copernicus during the 16 th century.

Image taken from http://hendrianusthe.wordpress.com

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3. THE SOLAR SYSTEM ●A central star: the Sun

Mercury is the smallest planet in the Solar System. It does not have atmosphere. It has a lot of craters

Inner planets (they are made up mostly of rocks) ● Planets (they orbit the Sun)

The Solar System is made up of

Venus is similar in size to the Earth. Its surface has the highest temperatures The Earth is the only planet w here life is known to exist. The Earth is at the correct distance from the Sun to make life possible.

Mars is red. It is the planet most similar to the Earth.

Outer planets (they are made up mostly of gases)

Jupiter is the biggest planet in the Solar System.

It has many satellites.

Saturn is surrounded of thousands of rings.

These rings are made up of millions of small particles.

Uranus has a blue-green colour. It has rings. Its rotation axis is nearly horizontal.

Neptune is blue. It is the outer planet with less satellites.

●Dwarf planets like Pluto and Eris. The difference betw een a planet and a dwarf planet is that a dw arf planet shares its orbit with other celestial bodies whereas a planet orbits on its own. ●Satellites, they are celestial bodies that orbit planets or smaller bodies. The outer planets have many satellites. The inner planets have few er satellites (Mercury and Venus have not got satellites). ●Comets, they are celestial bodies made of ice and dust. When a comet gets close to the Sun part of it evaporates pushing the dust and gas away from the comet. This forms the comet's tail. ●Asteroids, they are big pieces of rock. Many orbit the Sun between Mars and Jupiter forming the asteroid belt. ●Meteoroids are pieces of asteroids or comets that travel through space. When they enter a planet's atmosphere and they start to burn they are called meteors. When they crash into other planets they are called meteorites.

Image taken from http://www.fireballsinthesky.com.au

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4. GLOSSARY ENGLISH

CATALAN

Asteroids Asteroid belt Black hole Comets Constellation Dwarf planet Galaxy Geocentric theory Heavenly bodies Heliocentric theory Inner planets Jupiter Light Mars Mercury Meteor Meteorite Milky Way Neptune Outer planets Planets Pluto Satellites Saturn Size Solar System Stars Surroundings The Earth Uranus Venus

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5. ACTIVITIES THE

UNIVERSE, STARS AND GALAXIES

1. What is a galaxy?

2. What is the Milky Way? State one of its characteristics.

3. What does the Big Bang theory explain?

4. What are stars?

5. Why do stars emit light and heat?

6. Why do stars have different colours?

7. Why do stars look small to us? What are they really like? Very big or very small?

8. What star has the highest temperature? a) a blue star

b) a yellow star

c) a red star

9. Which is the correct order, starting with the smallest and ending with the largest? a) planet, star, galaxy

THEORIES

b) planet, galaxy, star

c) star, planet, galaxy

ABOUT THE STRUCTURE OF THE UNIVERSE

10. Indicate if the following statements belong to the heliocentric theory or to the geocentric theory: a) The Earth does not move. b) The Sun is at the centre of the universe. c) It was developed by Copernicus. d) It was developed by the Greeks. e) All heavenly bodies orbit around the Earth. f) All heavenly bodies orbit around the Sun. 11. Briefly explain the two theories about the structure of the universe.

THE SOLAR SYSTEM 12. Why comets only have tail when they are near the Sun?

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13. What can be found in between Mars and Jupiter?

14. Read the following statements and decide whether each one is true or false. Rewrite the false statements so that they become true: a) The Sun orbits the planets. b) The Solar System has eight planets. It is in the Milky Way. c) The biggest planet in the Solar System is Mars.

15. Which is the smallest planet in the Solar System?

Which is the biggest one?

Which is furthest from the Sun? 16. Copy and complete the diagram with these words: Earth, Universe, Solar System and Milky Way

D) C) B) A) Earth

17. What are the inner planets made up of? And the outer planets?

18. What are the heavenly bodies that orbit planets called?

19. Which is the difference between a planet and a dwarf planet? Write the name of two dwarf planets.

20. Why is life possible on Earth?

21. Why does Venus surface have the highest temperatures?

22. What planet is most similar to the Earth?

23. Which planets of the Solar System have rings?

24. Which planets of the solar system do not have satellites?

25. What is the asteroid belt?

26. Why do planets orbit the Sun instead of moving away from it?

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27. Each of the following features correspond to planets in the Solar System. Identify each of these planets: a) It is red. b) It is blue. c) Its surface has the highest temperatures. d) Its surface is full of craters. e) It has water on its surface. f) It is surrounded of thousand of rings. g) Its rotation axis is nearly horizontal. h) It is the biggest planet in the Solar System.

28. Read the following statements and decide whether each one is true or false. Rewrite the false statements so that they become true: a) Pluto and Eris are dwarf planets. b) The Milky Way is located in the Solar System. c) The Big Bang is a theory that explains how the universe was formed. d) Each galaxy is made up of one star and several planets.

29. Complete the table: Composition

Where are located?

satellites asteroids meteors comets

30. Read the following statements and decide whether each one is true or false. Rewrite the false statements so that they become true: a) The Sun orbits the planets. b) The Solar System has eight planets. It is in the Milky Way. c) The biggest planet in the Solar System is Mars. d) The biggest heavenly body in the Solar System is the Sun.

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31. By means of a telescope the following celestial bodies can be observed. Indicate what type of celestial bodies are each of them.

Image taken from http://www.xtec.cat

Image taken from http://en.wikipedia.org Image taken from http://sgaguilarjramos.blogspot.com.es

32. Write a definition and give an example of: a) Star b) Planet c) Satellite 33. Write a definition of: a) Comet b) Meteor c) Asteroid

34. Complete the following table about celestial bodies: Celestial body

Composition

Location

Example

Comet The Sun The Moon Asteroid Meteoroid

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UNIT 2. OUR PLANET THE EARTH CONTENTS 1.

The Earth´s movements

2.

The Earth's layers

3.

The Moon

4.

Eclipses and tides

5.

Glossary

6.

Activities

1. THE EARTH'S MOVEMENTS

Earth's movements

Rotation: It is the movement of the Earth around its axis (imaginary line that goes from the North to the South pole). This axis is tilted 24º.

The Earth spins anticlockwise.

The Earth takes 24 hours to complete one rotation.

Rotation is the reason why we have days and nights.

A day is the time a planet takes to spin on its own axis.

Image taken from http://roble.pntic.mec.es

Revolution: It is the movement of the Earth around the Sun. A year is the time a planet takes to orbit the Sun. The Earth takes 365 ¼ days to go once round the Sun. This is why every four years the year has an extra day. The years with 366 days are called leap years.

Revolution together w ith the Earth’s tilt is the reason why we have seasons.

Summer solstice (June 21st) the Northern Hemisphere is tilted towards the Sun, so it having its summer season (longer and warmer days). The southern hemisphere is tilted away from the Sun and is therefore having its winter season (shorter and colder days). At the North Pole there are 24 hours of daylight, whereas at the South Pole there are 24 hours of darkness.

Winter solstice (December 21st) the Southern Hemisphere is tilted towards the Sun, so it having its summer season (longer and warmer days). The northern hemisphere is tilted away from the Sun and is therefore having its winter season (shorter and colder days). At the South Pole there are 24 hours of daylight, whereas at the North Pole there are 24 hours of darkness.

Vernal equinox (March 21st) and autumnal equinox (September 23st) On these two days neither hemisphere is tilted towards the Sun. There is an equal amount of day and night.

Image taken from http://www.amsgrade4.com

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2. THE EARTH'S LAYERS

Atmosphere: It is a layer of gases that surrounds the Earth.

Hydrosphere: It is a layer of water on Earth.

The Earth's layers

Biosphere: It is the layer where living beings inhabit.

Geosphere: It is the solid layer of the Earth made up of rocks

3. THE MOON The size of the Moon is a Âź of the size of the Earth.

The Moon has no atmosphere.

The Moon does not emit its own light, but reflects the one from the Sun. The Moon orbits the Earth anticlockwise every 28 days and it rotates on its axis every 28 days.

This is why we always see the same side of the Moon.

The surface of the Moon has craters, lava plains (dark areas called seas), mountains and valleys.

3.1. THE LUNAR PHASES The Moon is illuminated because it reflects the light from the Sun. The part of the Moon facing the Sun is lit up. The part facing away from the Sun is in darkness.

We can only see the part of the Moon that is lit up. The lit part of the Moon that we see changes because it depends on the position of the Moon in its orbit.

The phases of the Moon are the different shapes of the lit part of the Moon that we see.

1.

New moon: the Moon is between the

Earth and the Sun, the dark half is facing us and so we cannot see it at all.

2.

First quarter

3.

Full moon: the Moon is directly opposite

the Sun. 4.

Image taken from http://www.lpi.usra.edu

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Last quarter

4. ECLIPSES AND TIDES An eclipse happens when the Earth, the Moon and the Sun are located in a straight line.

As the Moon is much smaller than the Earth solar eclipses can only be seen on a small part of the Earth.

Total eclipse : The Moon fully covers the Sun Image taken from http://www.terrastro.com

Solar eclipse It occurs w hen the Moon passes betw een the Sun and the Earth, and the Moon fully or partially covers the Sun. Eclipses

Partial eclipse The Moon partially covers the Sun Image taken from http://ventana-almundo.blogspot.com

Annular eclipse The Moon partially covers the Sun

Image taken from http://en.wikipedia.org

Lunar eclipse It occurs w hen the Earth passes betw een the Sun and the Moon, so the Moon does not get any sunlight.

Tides are the increase and decrease of the sea level due to the gravitational pull of the Moon.

The ocean is constantly moving from high tide to low tide, and vice-versa. Each day, there are two high tides and two low tides.

Image taken from http://en.wikipedia.org

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5. GLOSSARY ENGLISH

CATALAN

Atmosphere Axis Biosphere Eclipse Equinox Full Moon Geosphere Hydrosphere Lunar phases New Moon Revolution Rotation Seasons Solstice Tide Tilt Towards

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6. ACTIVITIES THE

EARTH'S MOVEMENTS

1. Suppose the Earth was spinning much more slowly, which difference would we notice?

2. The length of an Earth day is the time required for one a) Earth rotation

b) Earth revolution

c) Sun rotation

d) Sun revolution

3. Earth has seasons because a) the temperature of the Sun changes.

c) Earth's axis is tilted as it moves around the Sun

b) Earth rotates on its axis

d) the distance between the sun and the Earth changes

4. Can you explain why we have sometimes 29 days in February?

5. Complete the chart: Observable phenomena

Causes

The changing of days and nights The changing of the seasons 6. Define: a) Rotation: b) Revolution: c) Earth's axis: d) Day: e) Year: 7. What part of the Earth has 24 hours of daylight during the 21 st of June?

8. When are days and nights of equal length?

9. When does an hemisphere have its summer? And its winter?

10. What happens at the North Pole during the winter solstice?

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11. Look at the diagram below and answer the following questions: a) What season is having the northern hemisphere?

Why?

b) What season is having the southern hemisphere?

Why?

12. Draw a diagram with the Earth and the Sun when the northern hemisphere is having its summer.

THE

EARTH'S LAYERS

13. Each of the following lines correspond to one of the layers of the Earth. Identify each of them: a) Layer of water. b) Layer of gases. c) Solid layer of the Earth d) Layer where living things inhabit.

14. The following are elements that we can find on the Earth’s surface. Classify them into the layer of the Earth that they belong to. a) The water in a river b) The rocks on a mountain c) The waves in the sea d) The sand on the beach e) The air we breathe f) Rain g) The lake in the ‘Coves del Drach’ h) ‘El Puig Major’ i) The lynx j) YOU! THE MOON 15. Why do craters stay on the Moon and not on Earth?

16. In what direction does the Moon rotate: clockwise or anticlockwise?

17. What are the Moon's seas?

18. What is the name of the Moon when we cannot see it?

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19. When do we see a full moon?

20. Number and name the phases of the Moon:

a) b)

21. Does the Moon emit light? Then, why do we see the Moon?

22. Indicate using a drawing the two Moon's movements. State the length and direction of these 2 movements.

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23. Draw and name the 4 lunar phases on the diagram below:

24. Why we always see the same side of the Moon?

ECLIPSES

AND TIDES

25. What happens when the Moon passes between the Sun and the Earth?

26. When does a lunar eclipse occur?

27. Draw and name the three types of solar eclipse:

28. Looking at the diagram below, answer: a) What type of eclipse would person B see? b) What type of eclipse would person A see?

Moon B Sun

A

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Earth

29. Draw a diagram showing the arrangement of the Earth, Sun and the Moon when a lunar eclipse occurs.

30. a) What phenomenon can be observed in the following images? b) What causes it?

c) What difference in time there is between the two images?

31. Draw the Earth's rotation and indicate its main characteristics (axis, direction and length).

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32. Complete the following diagram with the seasons in the Northern hemisphere, equinoxes and solstices.

33. How many times have you been around the Sun?

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