Vocabulary communication optical fi bers technology telecommunications vehicle Picture Credits Every effort has been made to secure permission and provide appropriate credit for photogra
Trang 1Scott Foresman Science 4.19
Nonfi ction Main Idea and Details • Captions
• Labels
• Call Outs
• Glossary
Technology
ISBN 0-328-13914-9
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Scott Foresman Science 4.19
Nonfi ction Main Idea and Details • Captions
• Labels
• Call Outs
• Glossary
Technology
ISBN 0-328-13914-9
ì<(sk$m)=bdjbej< +^-Ä-U-Ä-U
Trang 21 What are some examples of technology
you use every day?
2 When you visit the doctor, how might
technology improve your visit?
3 What are some examples of modern
transportation systems?
improve our lives, but it can also cause harm Write to explain what some of the harmful effects of technology are Use details from the book to support your answer
details that help you understand the benefi ts of technology?
What did you learn?
Vocabulary
communication
optical fi bers
technology
telecommunications
vehicle
Picture Credits
Every effort has been made to secure permission and provide appropriate credit for photographic material
The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.
Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd).
5 Getty Images; 9 (BR) Lester Lefkowitz/Corbis, (TR) ©Stockbyte; 11 (TR) Getty Images; 12 (BL) Goodshoot.
Scott Foresman/Dorling Kindersley would also like to thank: Opener: NASA/DK Images; 14 (TR) National Maritime
Museum/DK Images.
Unless otherwise acknowledged, all photographs are the copyright © of Dorling Kindersley, a division of Pearson
ISBN: 0-328-13914-9
Copyright © Pearson Education, Inc All Rights Reserved Printed in the United States of America
This publication is protected by Copyright, and permission should be obtained from the publisher prior to any
prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic,
mechanical, photocopying, recording, or likewise For information regarding permission(s), write to
Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.
3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05
by Tess Mason
Trang 3Living With
Technology
You don’t need to be a scientist to use technology
In fact, you are probably using it right now! Is there a
light on in the room? Is there heat or air conditioning?
Technology is all around you Technology is the
knowledge, processes, and products that we use to
solve problems and make work easier It can help us
lead more productive lives It can also help us to be
safer and more comfortable
2
Although technology is intended to make life better, sometimes its side effects can be harmful For example, cars are very helpful technology However, cars can cause air pollution
Overall, most people think that technology has been more of a benefi t than a harm It can change the way people work Some machines may do jobs that people used to do Other machines may do jobs that are too dangerous for people to do This can bring about new inventions that were not possible before
Technology can lead to new jobs and new products
Think of how many products you use every day that are available because of technology
3
Trang 4Products of Technology
Look down What are you sitting on? It was probably
made through technology In fact, many things around
us are made using technology
This in-line skater probably is not aware of all the
kinds of technology he’s using In-line skates aren’t
found in nature They are made using a combination
of natural resources and technology
Technology helps make other equipment too The
skater’s helmet and his knee, elbow, and wrist guards all
contain plastic Plastic is made from chemicals It is a
product of technology
Even the clothing the skater is wearing is a result of
technology There may be cloth inside his knee, elbow,
and wrist guards This cloth could be made from nylon,
which is a kind of plastic His clothing may be made of
polyester, which is a thread created by chemicals The
frames and lenses of his glasses may be made from
plastic The skater is surrounded by technology
Technology can help keep us safe
The helmet and the knee, elbow, and wrist guards will help protect the skater if he falls.
Trang 5Pollution and Technology
Unfortunately, as companies manufacture products,
they also make pollution and waste Ordinarily, things
that are made in nature will decompose, or break down,
so they become part of the earth again Many materials
that are manufactured by people—not made by nature—
do not decompose Plastic foam is a material that does
not decompose
To help make up for this negative side effect of
technology, it is important to reuse materials made
through technology We should recycle materials such
as plastic and glass that cannot decompose on their own
Trash that does not decompose
fi lls up landfi lls,
so recycling is important for the environment.
6
Medicine has benefi ted greatly from technology
New tools developed through technology have changed medical care
At one time, surgery meant using small, sharp knives Today, if you need surgery, your doctor might
be able to use a laser instead For example, surgery on your eye can be done with a laser
Another way medical technology has improved
medicine is through the use of optical fi bers Optical
fi bers are very thin tubes that allow light to pass
through them By using tiny optical fi ber cameras, doctors can see inside the body without making large cuts New technology can help doctors to make smaller and fewer cuts This can help a patient to heal faster and to have less pain
Medical Technology
A single optical fi ber is so thin that it could fi t through the eye of a needle.
7
Trang 6The Technology of Food
Technology can help provide food We need a variety
of foods in order to be healthy Modern technology helps
us to plant, harvest, and grow food Fertilizers help plants
grow They also help produce larger crops than those that
would grow without chemicals Pesticides help keep
insects from eating the plants Machines help harvest the
crops The resulting variety of food provides a healthy
diet for us
However, the technology of food production has some
bad side effects Some fertilizers and pesticides can harm
the environment, animals, and even people As with other
technologies, companies are trying to improve food
technology while limiting the harmful side effects
Machines gather
crops of grain.
8
X rays and Beyond
X rays were discovered in 1895
by Wilhelm Roentgen In science,
X is a symbol for the unknown
Since Roentgen didn’t understand what he’d discovered at fi rst, he called it the X ray
X rays allow doctors to see inside the body without touching
it Doctors take X-ray pictures to help see problems such as broken bones In a dentist’s offi ce, X rays are used to help fi nd cavities
While X rays are helpful, they can also be harmful Too much exposure to X rays can cause burns and cancer
Magnetic resonance imaging (MRI) is a kind of technology that shows images from inside the body that X rays can’t show With an MRI, doctors can examine parts
of the body, such as joints, organs,
or blood vessels, without surgery
This X ray of the head and neck clearly shows the bones of the skull and the backbone.
MRI scans show images
of any part of the body from any direction You can see the brain here.
9
Trang 7Communication
And Transportation
Technology has improved the way we communicate
Communication is the process
of sending any kind of message from one place to another What would life be like without modern communication technology?
Suppose you wanted to send a message to a friend who lived in another city without using your phone or your computer You would have to send a letter or visit your friend in person
early telephone
Telephones throughout the years have made communication easier.
modern telephone cellular telephone
10
Before the computer, the typewriter was an important everyday communication tool
Computers make long-distance communication quick and easy.
Three things are necessary for good communication First you must send a message Then the message must be received Finally the message must be understood
We communicate in many ways
You can talk to someone in person
or, through the use of technology,
on a phone You can write a letter
or type an e-mail You can take a photograph or even make a video
We communicate every day in many ways
Communication technology makes this faster and easier than ever before
11
Trang 8Early communication
had to be done face to face
Later there was written
communication But it
took time to deliver
written communication
In the nineteenth century,
inventors began exploring ways
messages could be sent using
electricity The telegraph and the
telephone took only a few seconds to send messages
that used to take days or weeks Now you could talk
to someone far away without leaving the house!
Telecommunications are communications that are
done electronically A transmitter sends a signal This
signal carries information A receiver picks up the signal
and turns it into a clear message
By using communication satellites, we can send signals
from our phones, radios, TVs, and other devices all over
the world Satellites help in other ways too Everything from cars to planes can use satellites for navigation
Telecommunications
early telegraph machine
Satellite dishes send and collect signals.
12
Technology has improved our ability to get from one place to another Our transportation systems are faster and work better than ever before Transportation systems move people and goods from place to place
Usually, transportation systems use a vehicle A vehicle
carries people and goods There are many kinds of vehicles, including cars, ships, and planes Vehicles travel on land and water and through the air
As technology continues to advance, transportation becomes safer Engineers improve safety devices, such as seat belts and air bags They test these devices and make improvements Although the safety devices cost extra, they make traveling safer
Transportation
Airplanes have made worldwide travel faster.
13
Trang 9Thousands of years ago, we
used the Sun to tell time Now,
through modern technology,
we use clocks, watches, and
computers to measure time
In the past, transportation
systems were run by people
Now computer technology can
run many transportation systems
Computers keep the systems
operating smoothly and on time
All day long, we use technology without realizing it
From the bus we ride to the computer we use,
technology is all around us It lets us communicate with
nearly anyone in the world Technology makes working
easier It helps to feed us and to keep us healthy
Technology helps us to get from place to place faster
Overall, technology makes life better As technology
advances, we continue to manage the side effects
What new technology would you like to see? Jet cars
or even daily trips into space? As technology continues
to advance, we will continue to see its benefi ts
Technology is everywhere!
New technology could make space travel possible for more people
early clock
Trang 10communication the process of sending any
kind of message from one place to another
optical fi bers very thin tubes that allow light
to pass through them
and products that we use to solve problems and make work easier
telecommunications communications that are
done electronically
carries people and goods
16
1 What are some examples of technology
you use every day?
2 When you visit the doctor, how might
technology improve your visit?
3 What are some examples of modern
transportation systems?
improve our lives, but it can also cause harm Write to explain what some of the harmful effects of technology are Use details from the book to support your answer
details that help you understand the benefi ts of technology?
What did you learn?
Vocabulary
communication
optical fi bers
technology
telecommunications
vehicle
Picture Credits
Every effort has been made to secure permission and provide appropriate credit for photographic material
The publisher deeply regrets any omission and pledges to correct errors called to its attention in subsequent editions.
Photo locators denoted as follows: Top (T), Center (C), Bottom (B), Left (L), Right (R), Background (Bkgd).
5 Getty Images; 9 (BR) Lester Lefkowitz/Corbis, (TR) ©Stockbyte; 11 (TR) Getty Images; 12 (BL) Goodshoot.
Scott Foresman/Dorling Kindersley would also like to thank: Opener: NASA/DK Images; 14 (TR) National Maritime
Museum/DK Images.
Unless otherwise acknowledged, all photographs are the copyright © of Dorling Kindersley, a division of Pearson
ISBN: 0-328-13914-9
Copyright © Pearson Education, Inc All Rights Reserved Printed in the United States of America
This publication is protected by Copyright, and permission should be obtained from the publisher prior to any
prohibited reproduction, storage in a retrieval system, or transmission in any form by any means, electronic,
mechanical, photocopying, recording, or likewise For information regarding permission(s), write to
Permissions Department, Scott Foresman, 1900 East Lake Avenue, Glenview, Illinois 60025.
3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05