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HIGH SCHOOL SCIENCE TODAY

Textbook

FIRST YEAR

HIGH SCHOOL SCIENCE TODAY FIRST YEARTextbook

Philippine Copyright 2009 by DIWA LEARNING SYSTEMS INCAll rights reserved. Printed in the Philippines

Editorial, design, and layout by University Press of First Asia

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Exclusively distributed by DIWA LEARNING SYSTEMS INC 4/F SEDCCO 1 Bldg. 120 Thailand corner Legazpi Streets Legaspi Village, 1229 Makati City, Philippines Tel. No.: (632) 893-8501 * Fax: (632) 817-8700

ISBN 978-971-46-0097-3

REVIEWERCorazon B. Decella has a bachelor’s degree in Elementary Education major in Home Economics at the Philippine Normal University (PNU). She has a diploma in Science Education from Shizuoka University in Japan and a master’s degree in Teaching Science from the Eulogio Rodriguez Institute of Science and Technology in Sampaloc, Manila. Prof. Decella is also taking up a doctorate degree in Educational Administration at the Philippine Normal University. She taught science and religion at the Concordia College in Paco, Manila. Presently, she is an instructor at PNU.

PREFACE

Discoveries in science and technology in recent years have had a profound impact on our society. We are now able to communicate easier with the use of the Internet and cellular phones. We have found ways to replace damaged body parts through prostheses and organ transplants. People are continually developing new medicines to treat diseases that were once fatal. Scientists have been able to clone animals, find alternative fuel sources, explore the far reaches of outer space, and develop better materials for construction. Even the way we entertain ourselves has been affected by discoveries in science.

With all these fascinating discoveries, it is important that you understand the scientific principles behind such advancements. The High School Science Today series has been developed with two objectives in mind: to explain key scientific concepts clearly and accurately within a context of unifying themes; and to introduce you to the technology and research techniques which have resulted from the application of these scientific concepts.

The topics in each textbook are organized to keep key science concepts in clear view. In each chapter, you will find discussions on specific technological breakthroughs and the implications these developments have on our global community.

Understanding science requires that you observe the things around you, perform experiments to solve problems, and explain the reasons for your observation. Each textbook contains activities that will help you develop the skills necessary in learning science concepts meaningfully. These activities will provide you with hands-on learning experiences. You will be asked to predict, hypothesize, describe, make models, form conclusions, calculate, and measure with accuracy and precision.

As such, High School Science Today will enable you to keep pace with the ever-evolving world of science and technology. We invite you to take this journey with us—into the future and beyond.

TABLE OF CONTENTS

UNIT 1 THE WAYS OF SCIENCE

Chapter 1 An Introduction to Science and Technology1.1 The Impact of Science and Technology on Daily Living and Society ............... 21.2 Superstitions ...................................................................................................... 51.3 Thinking Skills .................................................................................................... 81.4 Local and Foreign Scientists ............................................................................ 131.5 How Science and Technology Affect Our Lives .............................................. 18

Chapter 2 Scientific Studies2.1 Serendipity ....................................................................................................... 212.2 Scientific Method ............................................................................................. 232.3 Presentation of Data ........................................................................................ 292.4 Measurement and Computation ..................................................................... 312.5 Conversion of Units ......................................................................................... 342.6 Laboratory Equipment in Biology, Chemistry, and Physics .......................... 40

UNIT 2 MATTER

Chapter 3 Properties and Classification of Matter3.1 Some Natural Phenomena Exhibited by Matter ............................................ 483.2 Properties of Matter ........................................................................................ 543.3 Classification of Matter: Substances ............................................................... 613.4 Classification of Matter: Mixtures .................................................................. 743.5 Methods of Separating Mixtures .................................................................... 783.6 Models of Matter ............................................................................................. 80

Chapter 4 Changes in Matter4.1 Physical Changes .............................................................................................. 874.2 Chemical Changes ............................................................................................ 904.3 Law of Conservation of Mass .......................................................................... 94

UNIT 3 ORGANISMS AND THEIR ENVIRONMENT

Chapter 5 Characteristics and Organization of Organisms5.1 Characteristics of an Organism .....................................................................1025.2 Cells: Building Blocks of Living Things .........................................................1075.3 Plant and Animal Cells ..................................................................................110

Chapter 6 Interaction between Living and Nonliving Things6.1 Ecological System ...........................................................................................1146.2 Food Chain and Food Web .............................................................................1186.3 Relationships among Organisms ..................................................................1226.4 Flow of Matter in the Ecosystem ..................................................................1276.5 Flow of Energy in the Ecosystem ..................................................................134

Chapter 7 Balance in Nature7.1 A Balanced Ecosystem ...................................................................................1377.2 Human Intervention and the Balance in Nature .........................................1427.3 Environmental Profiles ..................................................................................1447.4 Conservation of the Environment ................................................................150

UNIT 4 EARTH AND ITS CHANGES

Chapter 8 Resources of Earth8.1 Raw Materials from Land ..............................................................................1568.2 Raw Materials from Forests, Oceans, and Air ..............................................1638.3 Using Technology to Reduce Pollution .........................................................166

Chapter 9 Changes in the Hydrosphere9.1 Seawater .........................................................................................................1699.2 Movement of Ocean Water ............................................................................1719.3 Rivers ..............................................................................................................1759.4 Water Pollution ..............................................................................................177

Chapter 10 Changes in the Atmosphere10.1 Layers of the Atmosphere .............................................................................17910.2 Weather and Climate .....................................................................................18010.3 Convection Current .......................................................................................18610.4 Monsoons .......................................................................................................18710.5 Weather Forecasting ......................................................................................18810.6 Weather Disturbances ...................................................................................18910.7 Other Phenomena Related to Atmospheric Changes ..................................192

Chapter 11 Changes in the Lithosphere11.1 Theories about Changes in the Lithosphere .................................................19611.2 Folding and Faulting ......................................................................................20111.3 Rock Formation .............................................................................................20311.4 Soil Formation ...............................................................................................20611.5 Volcanic Eruptions .........................................................................................21011.6 Precautionary Measures Before, During, and After a Volcanic Eruption ...21211.7 Earthquakes ...................................................................................................21311.8 Precautionary Measures Before, During, and After an Earthquake ...........217

UNIT 5 EARTH, THE SOLAR SYSTEM, AND BEYOND Chapter 12 Earth12.1 Physical Features of Earth .............................................................................222 12.2 Size of Earth ...................................................................................................224 12.3 The Surface of Earth ......................................................................................22612.4 Earth’s Motions ..............................................................................................22912.5 The Moon ........................................................................................................232

Chapter 13 The Milky Way and Beyond13.1 Members of the Solar System .......................................................................23813.2 Asteroids, Comets, and Meteoroids ..............................................................24413.3 Star Groups ....................................................................................................247 13.4 Life Stages of a Star .......................................................................................251 13.5 Galaxies ..........................................................................................................252

UNIT 6 FORCE AND ENERGY

Chapter 14 Force, Motion, Work, and Machines14.1 Force ...............................................................................................................25814.2 Contact and Noncontact Forces ....................................................................26414.3 Motion: An Effect of Force on Matter ..........................................................27214.4 Work ...............................................................................................................28314.5 Simple Machines ............................................................................................285

Chapter 15 Energy15.1 Kinds of Energy .............................................................................................29515.2 Law of Conservation of Energy .....................................................................30115.3 Transformation of Energy .............................................................................30215.4 Heat Transfer .................................................................................................305

Chapter 16 Energy: Sources and Conservation16.1 Sources of Energy in the Philippines ............................................................31016.2 Energy Issues and Concerns ..........................................................................31716.3 Energy Conservation .....................................................................................321Glossary 325Bibliography 328Index 329

THE WAYS OF SCIENCE

Unit1

Curiosity leads to discovery. It is through curiosity that we explore our environment. Because of our curiosity, we find ways to answer these questions: “What makes up our world?” and “How can people maximize the use of our resources?”

Science will help you answer these questions using the scientific method. The scientific method will guide you in solving problems.

High School Science Today I2

Chapter 1 AN INTRODUCTION TO SCIENCE AND TECHNOLOGY

When you tell your friends how water affects plants or how gravity affects the ball, you are actually sharing scientific information. Sharing scientific information is a thinking skill. Scientists share information with each other. They also share this information to the public. This sharing of information results in people gaining knowledge. In addition to that, other people can verify the information they acquired by conducting observation and experimentation.

During the last decade, there were many important discoveries in the different fields of science. The applications of these discoveries have revolutionized our ways of living. Various new information that scientists have gathered through experimentation have led to technology advancements.

There are different ways one can gain knowledge of the nature of the physical world. Observation and experimentation are among these ways of gaining knowledge. To be able to observe and experiment properly, a scientist must possess certain skills, attitudes, and values, which can later on be applied to solve real-life problems.

1.1 THE IMPACT OF SCIENCE AND TECHNOLOGY ON DAILY LIVING AND SOCIETY

You deal with science every day; for instance, when you observe the effects of water on plants and the effects of gravity on a ball when you play volleyball. Observing is a basic thinking skill. It is important that you know how to observe properly.

What have you observed today?

Playing volleyball Watering plants

The Ways of Science 3

ACTIVITY 1.1 Activities Related to Science

Comparing is another thinking skill. You may describe the characteristics of objects by comparing them. After comparing the characteristics of objects, you may predict which object is better. For instance, comparison enables you to predict or judge which brand of toothpaste is better to use or what is the proper way of serving the ball to the other side of the court.

Making predictions is also a thinking skill. These predictions are based on earlier observations and previous knowledge. To verify predictions, scientists conduct experiments. For instance, after trying different brands of toothpaste, you will have an idea of how well a particular brand of toothpaste cleans the teeth. Or having tried different ways of serving the ball to the other side of the court, you will know which will best drive the ball to the other side of the net.

Through experiments, scientists have proven that most materials, such as metal, expand when heated and contract when cooled. This is why engineers, who use metal in building a bridge, study the climate of the area where it will be built. First, they consider the lowest and the highest temperatures to which the bridge will be exposed. Then, they estimate the effects of these temperatures on metal. From these estimates, the engineers can predict and decide how much space must be provided for the expansion of metal. To ensure the accuracy of these predictions, the engineers will refer to present and previous studies or will conduct experiments. In science, measurements should be precise and accurate.

Observing, sharing information, comparing, predicting, and experimenting are the thinking skills that you should practiced in your everyday life. These thinking skills are enhanced by scientific activities.

Activity 1.1 shows how you can enhance your thinking skills.

Materials

two thermometers, five-peso coin, medicine dropper, ink, salt, water, glass, alcohol lamp, beaker, match, tripod, wire gauze, iron stand, iron clamp, five different brands of two-ply toilet paper rolls

Procedure1. Your teacher will divide your class into six groups.


2. Refer to the list of activities below. Your teacher will assign one activity to each group.Activity 1 – Measure the temperature of the different areas of the school.Activity 2 – Toss a coin.Activity 3 – Mix the ink with cold water, lukewarm water, and hot water.Activity 4 – Determine the saturation of water with salt. Activity 5 – Measure the rise in temperature of water until it boils.Activity 6 – Verify the number of sheets of five different brands of two-ply

toilet paper rolls.

3. Solve the following problems for each activity:Activity 1: What do you think is the average temperature reading for the

different areas of the school? (Measure the temperature of the classroom, canteen, library, playground, etc.)

Activity 2: Predict the number of times that you can get a “head” or a “tail” when you flip a coin.

Activity 3: In which water temperature does a drop of ink spread fastest?Activity 4: How many grams of salt can be added to a glass half-filled with

water before the water becomes saturated?Activity 5: What is the rise in temperature (per minute) of water until it boils? Activity 6: Do different brands of two-ply toilet paper rolls have the same

number of sheets?

4. Predict the answer to the question assigned to your group.5. Conduct an experiment to check if your prediction is correct.6. You may write your observations based on the procedure of the experiment.

Tabulate the results and graph them afterward.7. Analyze your observations carefully.8. Prepare a written report. Present the results to the class.

Doing activities give you the opportunity to make a plan. There are activities that allow you to classify objects, tasks, and events. When you classify objects, tasks, and events, you organize or arrange them according to how you observe them. There are also activities that allow you to sequence objects, tasks, and events in a particular order. For instance, you may sequence events according to date. Another example of a sequence is the procedure you follow in doing an experiment or a life cycle of an organism.


Look at the following pictures. The pictures show the life cycle of a salmon from egg to maturity.

1.2 SUPERSTITIONS

You have heard older members of the family talked about unusual practices and beliefs shared to them by people from the previous generation. Some of these practices and beliefs have scientific explanations while others have no scientific basis at all. Beliefs and practices that are based on traditions and legends are called superstitions.

Let us study some old beliefs and practices. Determine whether the following beliefs and practices have scientific explanations or

are superstitions only. Put a in the box if the statement has a scientific explanation. Put an in the box if the statement is a superstition.

1. In Northern Luzon, there is a belief that if a pregnant woman eats eggs, her child will be born blind. In some provinces in the Visayas, people believe that a pregnant woman who eats twin bananas will deliver twins.

2. Some Filipino ethnic groups, especially those that live in the mountains, use certain herbs to treat illnesses and diseases. The use of herbs is a part of their belief that Mother Nature provides all our needs, including medicine.

Fig. 1.1 Life cycle of a salmon

fry

eggseyed eggs alevin

parr

smolt

adult


3. Some people follow certain practices to cure specific types of diseases. These practices include: the use of a girl’s first menstrual flow to treat pimples; the use of one’s first urine in the morning to cure certain eye diseases such as sore eyes; and the use of a quack doctor’s saliva to stop severe abdominal pain.

4. Some old folks in Southern Tagalog are fond of anting-anting or amulets, which they believe can protect them from physical injuries, such as gunshot wounds and stabbed wounds. They also claim that these amulets can ward off evil spirits.

5. Traditional farmers believe that when you see stars at night, then tomorrow will be a sunny day.

How true are these beliefs and practices?

1. There has been no scientific proof that birth defects, such as blindness, may be caused by eating eggs. As to eating twin bananas, it has not been proven that it will induce pregnant women to deliver twin babies.

2. Although the efficacy of some herbal medicines still has no scientific basis, there are ongoing studies that investigate the action of the chemical content of the herbal medicines. Some plants and herbs contain a derivative of the active substances found in commercially-produced medicines. In fact, the use of some of these herbal medicines, such as lagundi, is being promoted by the Department of Health.

3. The use of menstrual flow, urine, saliva, and other body fluids to cure certain diseases is dangerous and unhygienic. These body fluids may contain harmful bacteria that can cause more serious health problems.

4. Those people who believe in amulets tend to have a feeling of invincibility, making them believe in their physical capabilities to overcome obstacles. There is no scientific proof of the power of anting-anting.

Fig. 1.2 Different amulets


ACTIVITY 1.2 Identifying and Analyzing Superstitious Beliefs

5. Farmers are guided by changes in the environment. The belief that the presence of stars at night is an indication that a sunny day will follow has some truth to it because stars can be seen only when the sky is clear.

Traditional fishermen also believe that it is difficult to catch fish on a full moon. This can be true since fish do not stay near the water surface to feed during full moon. They are disturbed by the shadows cast on the water.

Many superstitious beliefs surfaced out of ignorance. People in the older times tended to ascribe to their gods certain events that could not be explained. Examples of these events are natural disasters and phenomena. Ancient people believed that disasters were the gods’ way of showing displeasure toward their ways.

In Activity 1.2, you will collect information about common beliefs and practices. The data will be analyzed if they have scientific basis.

Procedure1. Form six groups.2. Each group will discuss three superstitions.3. For each superstition, give a scientific reason why you should discontinue each

practice.4. Each group will discuss superstitions under six broad categories, as shown

below:Group 1 – Food Group 2 – Personal hygiene Group 3 – Pets and plants Group 4 – Natural phenomenaGroup 5 – Agricultural practicesGroup 6 – Birth or death

5. Assign a reporter to summarize the group discussion before the class.


1.3 THINKING SKILLS

When it was first suggested that Earth is round, very few people accepted the idea. One reason for rejecting the idea was that most people believed that if Earth is round, then everything on it, except those things at the top of it, would fall unless those things are held on the ground. Furthermore, people asked, “How could a person live on the underside of Earth with his or her head down all the time?”

So scientists pursued the study to determine Earth’s shape. They collected information about our planet that would directly or indirectly support their claim. As proofs whether for and against the issue were uncovered, the facts known and accepted by everybody changed.

Observing and Making Inferences

In the course of solving a problem, whether scouting for the best product or finding the best way to serve a ball, you have to make keen and accurate observations. Observation is the act of gathering information through the use of your senses. The information gathered is also called an observation. Observation may employ measurements and calculations. For example, when you look out the window and see raindrops fall, you say, “It is raining.” This statement is an observation. To gather more information by observing objects, you may use special tools to extend the power of your senses. For example, to extend the power of sight, you use tools or instruments such as magnifying lens, microscope, camera, or telescope. What instruments do you use to extend the power of your other senses?

Observations may be qualitative or quantitative. Qualitative observations consist of data that pertain to qualities or characteristics, and which are gathered through the perception of stimuli, such as scents and tastes. Quantitative observations consist of numerical data.

Do Activity 1.3 to learn more about making keen observations and stating inferences based on observations.

ACTIVITY 1.3 Observations and Inferences

Materials

weed, pail of water, shovel, 12 sheet of light-colored paperboard (cartolina)


Procedure1. Go out to a grassy area. Pick a weed and observe it. 2. Use a shovel and try to get the whole root system of the weed.

3. Wash the root system thoroughly.

4. Lay the weed on the light-colored cartolina.

5. Use your sense of sight, touch, and smell to describe the following parts: root system, stem, leaf, and flowers, if any. You may use a magnifying lens. (Note: In describing each part of the weed, consider its size, general shape, color, odor, and texture.)

6. Are there damaged leaves? What could have damaged those leaves?

7. Do you think the weed is healthy? Why or why not?

Those Black Spots

DID YOU KNOW that if you look closely at a newspaper photograph, you will see that it is actually made up of so many black dots of various sizes? Use a magnifying glass to examine a newspaper photograph.

The bigger dots merge to form dark shades in the photograph, while the smaller dots are spaced farther apart, leaving more white space to produce a lighter shade. Together, these black dots are actually a play of light and dark shades that produce a black-and-white newsprint photo.

How is this done? The process is called halftone, where different shades of a particular photograph are converted into varying sizes of dots. This is made possible by taking a shot of the original photograph through a special screen placed in contact with the film. Screening consists of a piece of transparent film with a diagonal pattern of lines. This screen has about 2 to 3 lines per millimeter. When printed, the resulting picture has the same number of dots per millimeter.

TECHNO FRONTIERS

When observing an object, it is important to record the characteristics of the object. A special camera may be used to record the object’s physical characteristics such as color and texture. In Activity 1.3, you used a magnifying lens to discover more details about the parts of the weed being examined. The magnifying lens extended the power of your sense of sight.

When observing things around you, you make inferences. An inference is a conclusion that is based on a study of facts of a case. For instance, when you knock on the door of your friend’s house and nobody answers, you can infer that nobody is home. If you see the water in a plastic container decreasing, you can infer that there is a hole or a crack on the container. In Activity 1.3, what inferences were you able to formulate after observing the weed?


Comparing and Contrasting

In addition to observing and making inferences, there are other skills that you must practice to perform scientific activities successfully. Comparing and contrasting are two such skills.

Do Activity 1.4 to know what comparing and contrasting are.

ACTIVITY 1.4 Skills Used in Science

Materials

paper, pen, measuring tape, weighing scale, standard table of height and weight by sex and age according to the Food and Nutrition Research Institute (FNRI)

Procedure1. Determine the height and weight of at least five of your classmates. Tabulate

your data below.

DATA TABLE 1.1 Name Age Sex Height Weight Classification

1. 2. 3. 4. 5.

2. Refer to the FNRI standard table of height and weight. See if your classmates’ height and weight are within the standard range.a. What skills did you use to perform the activity? b. Cite other instances that require the skills you used.c. What tools did you use to determine height? Describe these tools. d. Compare the average height of the boys with the girls.e. What statement or inference can you make after comparing the average

height of boys and girls?

From the activity, you can state that the height and the weight of your classmates differ as to age and sex. Do you know the reasons for these differences?


Determining Cause and Effect

There are many events that you have observed. What causes these events to happen? What are the effects of these events on people and the environment? Many observers usually make wrong conclusions because they do not analyze an event thoroughly. By identifying the cause and the effect of any event, you can find a logical answer to any event.

Perform the following activity and determine what causes the sprouting of mongo seeds.

ACTIVITY 1.5 What Happened to the Seeds?

Materials

two same-sized sandwich bags, two pieces of same-sized cheesecloth, 20 mongo seeds, stapler, staple wire

Procedure1. On the first day, prepare the following setups.

2. On day two, open the two sandwich bags. What happened to the mongo seeds in sandwich bag 1? Explain.

3. What happened to the mongo seeds in sandwich bag 2? Explain.

The activity you performed enabled you to determine the cause and the effect of the germination of mongo seeds. Determining cause and effect is important when you do an experiment. Recall what variables are. What are the variables used in Activity 1.5? Which variable causes the germination of mongo seeds?

Fig. 1.3 A dry cheesecloth (with 10 mongo seeds inside)

Fig. 1.4 A wet cheesecloth (with 10 mongo seeds inside)

sandwich bags

staple wires


ACTIVITY 1.6 Estimating

Estimating and Measuring

In performing scientific investigations, you need to measure quantities such as the height of a person. Measurements were used even during the time of our ancestors. Our ancestors used body parts for measurement. Examples of these units of measurements are dipa, dangkal, and dali. Dipa is the measurement from the tip of the middle finger of one hand to the tip of the middle finger of the other hand when the arms are fully stretched sideways. Dangkal is the distance between the tip of the thumb and the tip of the little finger when the hand is fully stretched. Dali is the length from the tip of the thumb to its first segment.

What problems may occur when body parts are used to measure objects or distances? Find out the answer in Activity 1.6.

Material

measuring tape

Procedure1. Measure some of your body parts in centimeters.

a. Width of an index finger b. Length of a footc. Distance from the tip of the thumb to its first segment (dali)d. Distance between the tip of the thumb and the tip of the little finger

(dangkal)e. Distance between the tip of the middle finger of one hand and the tip of

the middle finger of the other hand when the arms are stretched sideways (dipa)

2. Estimate the length of the following objects in Data Table 1.2 using your body parts. Tabulate your data.

DATA TABLE 1.2

Object Lengthscience book _______________ daliclassroom _______________ dipateacher’s table _______________ dangkalpencil _______________ dalihallway _______________ dipa


3. Compare your estimates with those of your seatmate.4. What is the advantage of estimating? disadvantage of estimating?

You know that people have different sizes of body parts. If you use your body parts for measurement, you will not always get the same results. For instance, if a six-year-old boy measured his bed using dangkal, the result would no longer be true if his father will measure the same bed using the latter’s hand. This is the reason why standard tools of measurement are used in measuring objects.

1.4 LOCAL AND FOREIGN SCIENTISTS

Scientists possess positive attitudes and values that aid them in solving problems. What attitudes and values must a scientist possess?

Attitudes and Values that a Scientist Must Possess

1. A scientist is curious about the world.Curiosity enables a scientist to try to discover

more about the things around him or her. Galileo Galilee’s inquisitive nature led to his invention of the telescope which he used to observe outer space. Using the telescope, Galileo discovered the satellites of Jupiter, the craters on Earth’s moon, and the sunspots. This invention also made him the first person to study the moon, the sun, the planets, and the stars.

2. A scientist is logical and systematic.This attitude enables a scientist to plan his or her work in an

orderly way. Scientists became fascinated with the structure of genes after Gregor Mendel formulated the principles of heredity. These principles were a result of logical experimental methods and accurate record keeping. Mendel employed a systematic way of studying traits. For instance, he studied the inheritance of only one, then two, and finally three traits at a time. From his accurate records, he was able to see patterns from which traits would appear.

Fig. 1.5 Galileo and his telescope

Fig. 1.6 Gregor Mendel


3. A scientist is open-minded.Open-mindedness is an attitude that allows a scientist

to look at other possibilities. Johannes Kepler was hired to establish proof that planets moved along perfect circles. But being the open-minded person that he was, he dropped the idea after 15 years of work upon discovering an evidence that planets followed elliptical orbits. His ability to reverse his judgment led to more interesting discoveries.

Fig. 1.7 Johannes Kepler4. A scientist is intellectually honest.

This attitude allows a scientist to recognize the work done by other scientists before him or her. This attitude is also shown by reporting data truthfully. Isaac Newton acknowledged the fact that he built his laws of motion on the past works of Galileo and other scientists. It was not a hidden fact that his first law was very much like Galileo’s concept of inertia. Never claiming that he worked out physical laws on his own, Newton gave credit to the contributions of Galileo and other earlier physicists, saying that he was able to expand his vision “by standing on the shoulders of giants.”

5. A scientist works hard and is persistent.This attitude enables a scientist to continue with a project

despite obstacles and failures. Marie Curie, together with her husband Pierre Curie, worked long and hard on their research on radioactivity. They had to work on several thousands of kilograms of uranium ore to get a tenth of a gram of pure radium. Marie carried on even after her husband’s death until she discovered radium and polonium, both radioactive elements. For this achievement, she won the Nobel Prize twice.

Fig. 1.8 Isaac Newton

6. A scientist does not jump to conclusions.This attitude enables the scientist to withhold his or her

judgment until the tests have been completed. This means that scientists do not accept ideas until after an exhaustive investigation has been performed.

John Dalton was not the first to theorize that the atom was the smallest particle of matter, but he was the first to show proof to back up this idea. His atomic theory was supported by an exhaustive collection of experimental evidence.

Fig. 1.10 John Dalton

Fig. 1.9 Marie Curie


7. A scientist is creative and thinks critically.Being creative enables a scientist to come up with new

concepts which lead to discoveries that traditional scientists have overlooked. Albert Einstein was a 26-year-old clerk in the Swiss patent office when he challenged Newton’s fundamental assumptions of space and time. He developed his theory of relativity because he dared to go beyond what was acceptable then. He worked on several experiments and established links that others preferred to stay away from. He viewed things from a different perspective.

8. A scientist is rational.Dr. Ricardo Lantican is a Filipino scientist who is an

expert in the field of plant breeding. He recognized the need to address the worldwide problem of food sufficiency. With this goal in mind, he developed ways to improve the growth of different varieties of plants in the Philippines and other countries of East and South Asia. One of his important works is a research study on the cytoplasmic inheritance of hypersensitivity to a disease in corn.

9. A scientist perseveres in his or her work until he or she is sure of the results.

For five decades, Dr. Luz Oliveros-Belardo pursued her research on natural products and Philippine essential oils. Through her logical and systematic study, more natural products were developed and herbal medications were further improved. She continued her work until satisfactory results were attained.

Fig. 1.11 Albert Einstein

Fig. 1.12 Dr. Ricardo Lantican

10. A scientist tries new approaches to arrive at better solutions.Almost every day, advances in science and technology enable people to improve

ways of doing things. From these new ideas and concepts, a scientist is able to determine what methods or techniques are best adopted.

Perform Activity 1.7 and determine how you can apply scientific attitudes and values in your daily activities.

Fig. 1.13 Dr. Luz Oliveros-Belardo


ACTIVITY 1.7 Applying Scientific Attitudes and

Values in Your Daily Activities

Procedure1. Your teacher will divide your class into five groups.2. Refer to the attitudes and values of scientists given in the preceding

discussion. Your teacher will assign two scientific attitudes to each group.3. Answer this question through role-playing: How can you apply these attitudes

and values to your daily activities?

Contributions of Outstanding Filipino Scientists

Filipino scientists and inventors have contributed in the advancement of science and technology. The following are some Filipino scientists and their achievements.

1. Gregorio Y. Zara invented the television-telephone or videophone, a device that enables people to see each other on the television screen while talking over the telephone.

2. Dr. Fe del Mundo, a renowned pediatrician, designed an improvised incubator which popularized the use of artificial light for newborns. Her invention went on a continuing trial stage until it was proven effective.

3. Dr. Ramon Gustilo, an orthopedic surgeon, is renowned for the many artificial joints he invented. In fact, Dr. Gustilo has patented at least 10 inventions for artificial bone replacements.

4. Teresita Harina-Borromeo of the University of the Philippines−Los Baños (UPLB) employed methods to improve the quality of rice varieties.


5. Benito Vergara is a plant physiologist. He is best known for his manual for growing rice, A Farmer’s Primer on Growing Rice. This manual has been published in nine Philippine languages and 33 Asian, African, and Latin-American languages.

6. Ruben L. Villareal, an agriculture-based researcher, looked into ways to improve different farming methods.

7. Carmen L. Intengan contributed substantially to the field of nutrition research.

Do you know other Filipino scientists who greatly contributed to science and technology?

Although the different inventions of scientists have improved the quality of life, they also brought lots of problems to the society. For instance, gasoline, which fuels engines, pollutes the environment. Refrigerators and air conditioners give off chemicals that contribute to the destruction of the ozone layer. The atomic and hydrogen bombs have destroyed life.

Do the following activity and find out if technology is a boon or a bane.

ACTIVITY 1.8 Technology: Boon or Bane?

Materials

old magazines, paperboard (cartolina) or paper folder, pair of scissors, paste


Since technology has something to do with problems in the society, it is necessary to have a deeper understanding of how science and technology work. This will guide you in making responsible decisions.

1.5 HOW SCIENCE AND TECHNOLOGY AFFECT OUR LIVES

Living in today’s world has become more convenient than in the past. There are gadgets that help us do work easier and faster. This is because of the influence of science and technology.

Science is a systematized body of knowledge that is developed through observations, researches, and experimentations. Scientists, who are engaged in pure science, do thorough researches to answer questions about nature. Their researches yield new knowledge. Technology, on the other hand, is the practical application of science to everyday life.

Technology may come in the form of new products, such as antibiotics or processed food and gadgets or devices (computers and sewing machines). Technology also deals with different processes such as fermentation, pasteurization, and cloning.

Technology is a science being put to practical use. Take the case of Thomas Alva Edison, one of America’s most famous inventors. His observation that a thin wire would glow when an electric current passed through it, led him to develop the first electric light bulb.

The computer is another technological breakthrough that has a remarkable impact on modern living. Today, computers are used everywhere––offices, libraries, schools, banks, malls, and hospitals. They make work a lot easier, faster, and more precise and accurate.

The principles behind the operation of computers have many applications. For instance, when you dial a number on the telephone, the telephone system uses a computer to search for that number. Even direct-dial services use computers to enable your telephone to connect immediately with other telephone networks worldwide.

Fig. 1.14 The first electric light bulb

Procedure1. Cut out pictures or news items related to different products of technology from

old magazines. Paste these pictures on the paperboard (cartolina). 2. On each picture, write the advantages and disadvantages of the product. State

whether the product is used in your community or not.3. Write slogans about technology and its use.


ACTIVITY 1.9 Science, Technology, and Me

The computers installed by banks that let you make transactions round-the-clock have also become an indispensable banking tool. These computer-controlled automated teller machines (ATMs) allow you to make transactions from almost anywhere in the country or even worldwide.

Supermarkets use computers as well. Have you ever wondered what those seemingly insignificant black-and-white stripes printed on the packages of most products are? They are

actually coded messages that tell the name, manufacturer, size, and price of the items in a package. They are called bar codes. An electromagnetic device called a scanner enables the computer to read the code on an item and send information about it back to the computer. The computer then interprets the code and relays the price of the item to the cash register. At the same time, the computer also records that such an item has been bought. It becomes easy for businessmen to tally and make an inventory of the items sold.

One of the most interesting developments in computer technology is the Internet, a network connecting several computer networks based on a common addressing system and communications protocol. The Internet is used not only to send electronic mail (or e-mail), but also to navigate various Internet sites. It has proven to be an effective way to communicate with people in different parts of the world and to conduct research.

In the United States of America, several nonprofit advocacy organizations have teamed up with a dozen Internet companies in an effort to launch consumer education campaigns.

Technology has made it possible to shorten certain processes. As a result, life has been made easier by devices produced by technology.

Do the following activity and identify gadgets that make life better.

Fig. 1.15 ATM

Fig. 1.16 A bar code of a product being scanned.

Fig. 1.17 The Internet makes certain tasks easier.

Procedure

List 10 gadgets found in your school (classroom, laboratory, canteen, library, etc.). Describe how these gadgets make your school activities better, that is, faster, easier, and more accurate.


Chapter Review

I. Enriching Your Science Vocabulary Choose from the box the scientific attitudes and values that are described in the

following situations. Write your answer on the blank space.

Creativity Open-mindedness Curiosity Resourcefulness Intellectual honesty Persistence

_______________ 1. Accepting the correct ideas of other scientists_______________ 2. Making full use of available materials _______________ 3. Reporting data truthfully _______________ 4. Looking at a question or a problem from a nontraditional or

nonconventional point of view_______________ 5. Inquisitive attitude in trying to discover more things

II. Assessing Your KnowledgeA. Match the following observations with the possible inferences. Write the letters only.

Observations Inferences _____ 1. Her eyes are red. a. The mango is not ripe._____ 2. The mango is green. b. There is a stranger outside._____ 3. The teacher smiled. c. An adobo dish is being repared._____ 4. The dog is barking. d. She likes the answer._____ 5. I smell adobo from the kitchen. e. She has sore eyes.

B. Identify whether the situation describes a scientific truth or a superstition. Explain your answer on a separate sheet of paper.

1. On your way to school, a black cat crossed your path. It rained on that same day and you got soaked. You were not able to go to school the next day because you were down with fever. You blame the black cat for your misfortune.

2. On the night before your periodical test, you and your friends stayed up late to study. Before going to sleep, your mother advised you to place a book under your pillow. Thinking that this might help, you followed your mother’s advice. When the test results came, you were pleased to know that you and your friends passed.

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Technology

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