HIGH SCHOOL SCIENCE TODAY         FIRST YEAR         Textbook
HIGH SCHOOL SCIENCE TODAYFIRST YEARTextbookPhilippine Copyright 2009 by DIWA LEARNING SYSTEMS INCAll rights reserved. Prin...
P R E FA C E     Discoveries in science and technology in recent years have had a profound impact onour society. We are no...
TABLE OF CONTENTSUNIT 1      THE WAYS OF SCIENCEChapter 1   An Introduction to Science and Technology1.1         The Impac...
Chapter 7    Balance in Nature7.1          A Balanced Ecosystem .............................................................
Chapter 13     The Milky Way and Beyond13.1           Members of the Solar System ...........................................
Unit                                                                                       1THE WAYS OF SCIENCE     Curios...
Chapter             1                     AN INTRODUCTION       TO   SCIENCE      AND   TECHNOLOGY     During the last dec...
Comparing is another thinking skill. You may describe the characteristics of objectsby comparing them. After comparing the...
2.   Refer to the list of activities below. Your teacher will assign one activity to           each group.           Activ...
Look at the following pictures. The pictures show the life cycle of a salmon from egg tomaturity.                         ...
3. Some people follow certain practices to cure specific types of diseases. These       practices include: the use of a gir...
5. Farmers are guided by changes in the environment. The belief that the presence       of stars at night is an indication...
1.3 THINKING SKILLS     When it was first suggested that Earth is round, very few people accepted the idea.One reason for r...
Procedure     1. Go out to a grassy area. Pick a weed and observe it.     2. Use a shovel and try to get the whole root sy...
Comparing and Contrasting     In addition to observing and making inferences, there are other skills that you mustpractice...
Determining Cause and Effect     There are many events that you have observed. What causes these events to happen?What are ...
Estimating and Measuring     In performing scientific investigations, you need to measure quantities such as theheight of a...
3.   Compare your estimates with those of your seatmate.        4.   What is the advantage of estimating? disadvantage of ...
3.    A scientist is open-minded.          Open-mindedness is an attitude that allows a scientist     to look at other pos...
7.    A scientist is creative and thinks critically.          Being creative enables a scientist to come up with new     c...
Applying Scientific Attitudes and                     ACTIVITY 1.7       Values in Your Daily Activities     Procedure     ...
5. Benito Vergara is a plant physiologist. He is best                                   known for his manual for growing r...
Procedure      1. Cut out pictures or news items related to different products of technology from          old magazines. ...
The computers installed by banks that let you make transactions                    round-the-clock have also become an ind...
Chapter ReviewI.    Enriching Your Science Vocabulary      Choose from the box the scientific attitudes and values that are...
Upcoming SlideShare
Loading in …5
×

Hssttx1

1,464 views

Published on

Published in: Technology, News & Politics
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,464
On SlideShare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
15
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Hssttx1

  1. 1. HIGH SCHOOL SCIENCE TODAY FIRST YEAR Textbook
  2. 2. HIGH SCHOOL SCIENCE TODAYFIRST YEARTextbookPhilippine Copyright 2009 by DIWA LEARNING SYSTEMS INCAll rights reserved. Printed in the PhilippinesEditorial, design, and layout by University Press of First AsiaNo part of this publication may be reproduced or transmitted in any form or by any meanselectronic or mechanical, including photocopying, recording, or any information storage andretrieval systems, without permission in writing from the copyright owner. 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 978-971-46-0097-3REVIEWERCorazon B. Decella has a bachelor’s degree in Elementary Education major in Home Economics at thePhilippine Normal University (PNU). She has a diploma in Science Education from Shizuoka Universityin Japan and a master’s degree in Teaching Science from the Eulogio Rodriguez Institute of Scienceand Technology in Sampaloc, Manila. Prof. Decella is also taking up a doctorate degree in EducationalAdministration at the Philippine Normal University. She taught science and religion at the ConcordiaCollege in Paco, Manila. Presently, she is an instructor at PNU.
  3. 3. P R E FA C E Discoveries in science and technology in recent years have had a profound impact onour society. We are now able to communicate easier with the use of the Internet and cellularphones. We have found ways to replace damaged body parts through prostheses and organtransplants. People are continually developing new medicines to treat diseases that wereonce fatal. Scientists have been able to clone animals, find alternative fuel sources, explorethe far reaches of outer space, and develop better materials for construction. Even the waywe entertain ourselves has been affected by discoveries in science. With all these fascinating discoveries, it is important that you understand the scientificprinciples behind such advancements. The High School Science Today series has beendeveloped with two objectives in mind: to explain key scientific concepts clearly andaccurately within a context of unifying themes; and to introduce you to the technology andresearch 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 theimplications these developments have on our global community. Understanding science requires that you observe the things around you, performexperiments to solve problems, and explain the reasons for your observation. Eachtextbook contains activities that will help you develop the skills necessary in learningscience concepts meaningfully. These activities will provide you with hands-on learningexperiences. You will be asked to predict, hypothesize, describe, make models, formconclusions, 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—intothe future and beyond.
  4. 4. TABLE OF CONTENTSUNIT 1 THE WAYS OF SCIENCEChapter 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 .............................................. 18Chapter 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 .......................... 40UNIT 2 MATTERChapter 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 ............................................................................................. 80Chapter 4 Changes in Matter4.1 Physical Changes .............................................................................................. 874.2 Chemical Changes ............................................................................................ 904.3 Law of Conservation of Mass .......................................................................... 94UNIT 3 ORGANISMS AND THEIR ENVIRONMENTChapter 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 ..................................................................................110Chapter 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
  5. 5. 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 ................................................................150UNIT 4 EARTH AND ITS CHANGESChapter 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 .........................................................166Chapter 9 Changes in the Hydrosphere9.1 Seawater .........................................................................................................1699.2 Movement of Ocean Water............................................................................1719.3 Rivers ..............................................................................................................1759.4 Water Pollution ..............................................................................................177Chapter 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 ..................................192Chapter 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 ...........217UNIT 5 EARTH, THE SOLAR SYSTEM, AND BEYONDChapter 12 Earth12.1 Physical Features of Earth .............................................................................22212.2 Size of Earth ...................................................................................................22412.3 The Surface of Earth ......................................................................................22612.4 Earth’s Motions..............................................................................................22912.5 The Moon........................................................................................................232
  6. 6. Chapter 13 The Milky Way and Beyond13.1 Members of the Solar System .......................................................................23813.2 Asteroids, Comets, and Meteoroids ..............................................................24413.3 Star Groups ....................................................................................................24713.4 Life Stages of a Star .......................................................................................25113.5 Galaxies ..........................................................................................................252UNIT 6 FORCE AND ENERGYChapter 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 ............................................................................................285Chapter 15 Energy15.1 Kinds of Energy .............................................................................................29515.2 Law of Conservation of Energy .....................................................................30115.3 Transformation of Energy .............................................................................30215.4 Heat Transfer .................................................................................................305Chapter 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
  7. 7. Unit 1THE WAYS OF SCIENCE Curiosity leads to discovery. It is through curiosity that we explore our environment. Becauseof our curiosity, we find ways to answer these questions: “What makes up our world?” and “Howcan people maximize the use of our resources?” Science will help you answer these questions using the scientific method. The scientificmethod will guide you in solving problems.
  8. 8. Chapter 1 AN INTRODUCTION TO SCIENCE AND TECHNOLOGY During the last decade, there were many important discoveries in the different fields ofscience. The applications of these discoveries have revolutionized our ways of living. Variousnew information that scientists have gathered through experimentation have led to technologyadvancements. 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 ableto observe and experiment properly, a scientist must possess certain skills, attitudes, andvalues, 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 wateron plants and the effects of gravity on a ball when you play volleyball. Observing is a basicthinking skill. It is important that you know how to observe properly. What have you observed today?Playing volleyball Watering plants 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 thinkingskill. Scientists share information with each other. They also share this information to thepublic. This sharing of information results in people gaining knowledge. In addition tothat, other people can verify the information they acquired by conducting observation andexperimentation.2 High School Science Today I
  9. 9. Comparing is another thinking skill. You may describe the characteristics of objectsby comparing them. After comparing the characteristics of objects, you may predict whichobject is better. For instance, comparison enables you to predict or judge which brand oftoothpaste is better to use or what is the proper way of serving the ball to the other side ofthe court. Making predictions is also a thinking skill. These predictions are based on earlierobservations and previous knowledge. To verify predictions, scientists conductexperiments. For instance, after trying different brands of toothpaste, you will have an ideaof how well a particular brand of toothpaste cleans the teeth. Or having tried different waysof serving the ball to the other side of the court, you will know which will best drive the ballto 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 inbuilding a bridge, study the climate of the area where it will be built. First, they considerthe lowest and the highest temperatures to which the bridge will be exposed. Then, theyestimate the effects of these temperatures on metal. From these estimates, the engineerscan predict and decide how much space must be provided for the expansion of metal. Toensure the accuracy of these predictions, the engineers will refer to present and previousstudies or will conduct experiments. In science, measurements should be precise andaccurate. Observing, sharing information, comparing, predicting, and experimenting are thethinking skills that you should practiced in your everyday life. These thinking skills areenhanced by scientific activities. Activity 1.1 shows how you can enhance your thinking skills. ACTIVITY 1.1 Activities Related to Science 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 Procedure 1. Your teacher will divide your class into six groups. The Ways of Science 3
  10. 10. 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 allowyou to classify objects, tasks, and events. When you classify objects, tasks, and events, youorganize or arrange them according to how you observe them. There are also activities thatallow you to sequence objects, tasks, and events in a particular order. For instance, you maysequence events according to date. Another example of a sequence is the procedure youfollow in doing an experiment or a life cycle of an organism.4 High School Science Today I
  11. 11. Look at the following pictures. The pictures show the life cycle of a salmon from egg tomaturity. adult smolt parr fry eggs eyed eggs alevin Fig. 1.1 Life cycle of a salmon 1.2 SUPERSTITIONS You have heard older members of the family talked about unusual practices and beliefsshared to them by people from the previous generation. Some of these practices and beliefshave scientific explanations while others have no scientific basis at all. Beliefs and practicesthat 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 orare superstitions only. Put a in the box if the statement has a scientific explanation. Putan 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. The Ways of Science 5
  12. 12. 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 amulets6 High School Science Today I
  13. 13. 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. Thiscan be true since fish do not stay near the water surface to feed during full moon. They aredisturbed by the shadows cast on the water. Many superstitious beliefs surfaced out of ignorance. People in the older times tendedto ascribe to their gods certain events that could not be explained. Examples of these eventsare 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. Thedata will be analyzed if they have scientific basis. ACTIVITY 1.2 Identifying and Analyzing Superstitious Beliefs Procedure 1. 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 phenomena Group 5 – Agricultural practices Group 6 – Birth or death 5. Assign a reporter to summarize the group discussion before the class. The Ways of Science 7
  14. 14. 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, theneverything on it, except those things at the top of it, would fall unless those things are heldon the ground. Furthermore, people asked, “How could a person live on the underside ofEarth with his or her head down all the time?” So scientists pursued the study to determine Earth’s shape. They collected informationabout our planet that would directly or indirectly support their claim. As proofs whether forand 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 thebest way to serve a ball, you have to make keen and accurate observations. Observation isthe act of gathering information through the use of your senses. The information gatheredis also called an observation. Observation may employ measurements and calculations. Forexample, when you look out the window and see raindrops fall, you say, “It is raining.” Thisstatement is an observation. To gather more information by observing objects, you may usespecial 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 consistof data that pertain to qualities or characteristics, and which are gathered through theperception of stimuli, such as scents and tastes. Quantitative observations consist ofnumerical data. Do Activity 1.3 to learn more about making keen observations and stating inferencesbased on observations. ACTIVITY 1.3 Observations and Inferences Materials 1 weed, pail of water, shovel, 2 sheet of light-colored paperboard (cartolina)8 High School Science Today I
  15. 15. Procedure 1. 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? 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 colorand texture. In Activity 1.3, you used a magnifying lens to discover more details about theparts of the weed being examined. The magnifying lens extended the power of your sense ofsight. When observing things TECHNO FRONTIERSaround you, you makeinferences. An inference is Those Black Spotsa conclusion that is based on DID YOU KNOW that if you look closely at a newspapera study of facts of a case. For photograph, you will see that it is actually made up of soinstance, when you knock on the many black dots of various sizes? Use a magnifying glass todoor of your friend’s house and examine a newspaper photograph.nobody answers, you can infer The bigger dots merge to form dark shades in thethat nobody is home. If you see photograph, while the smaller dots are spaced farther apart, leaving more white space to produce a lighter shade. Together,the water in a plastic container these black dots are actually a play of light and dark shadesdecreasing, you can infer that that produce a black-and-white newsprint photo.there is a hole or a crack on the How is this done? The process is called halftone, wherecontainer. In Activity 1.3, what different shades of a particular photograph are convertedinferences were you able to into varying sizes of dots. This is made possible by takingformulate after observing the a shot of the original photograph through a special screen placed in contact with the film. Screening consists of aweed? 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. The Ways of Science 9
  16. 16. Comparing and Contrasting In addition to observing and making inferences, there are other skills that you mustpractice to perform scientific activities successfully. Comparing and contrasting are twosuch 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) Procedure 1. 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 differas to age and sex. Do you know the reasons for these differences?10 High School Science Today I
  17. 17. 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 observersusually make wrong conclusions because they do not analyze an event thoroughly. Byidentifying 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 mongoseeds. 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 Procedure 1. On the first day, prepare the following setups. staple wires sandwich bags Fig. 1.3 A dry cheesecloth Fig. 1.4 A wet cheesecloth (with 10 mongo seeds inside) (with 10 mongo seeds inside) 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 thegermination of mongo seeds. Determining cause and effect is important when you do anexperiment. Recall what variables are. What are the variables used in Activity 1.5? Whichvariable causes the germination of mongo seeds? The Ways of Science 11
  18. 18. Estimating and Measuring In performing scientific investigations, you need to measure quantities such as theheight of a person. Measurements were used even during the time of our ancestors. Ourancestors used body parts for measurement. Examples of these units of measurements aredipa, dangkal, and dali. Dipa is the measurement from the tip of the middle finger of onehand to the tip of the middle finger of the other hand when the arms are fully stretchedsideways. Dangkal is the distance between the tip of the thumb and the tip of the littlefinger when the hand is fully stretched. Dali is the length from the tip of the thumb to itsfirst segment. What problems may occur when body parts are used to measure objects or distances?Find out the answer in Activity 1.6. ACTIVITY 1.6 Estimating Material measuring tape Procedure 1. Measure some of your body parts in centimeters. a. Width of an index finger b. Length of a foot c. 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 Length science book _______________ dali classroom _______________ dipa teacher’s table _______________ dangkal pencil _______________ dali hallway _______________ dipa12 High School Science Today I
  19. 19. 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 formeasurement, you will not always get the same results. For instance, if a six-year-old boymeasured his bed using dangkal, the result would no longer be true if his father will measurethe same bed using the latter’s hand. This is the reason why standard tools of measurementare 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 Possess1. 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. Fig. 1.5 Galileo and his telescope 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. 1.6 Gregor Mendel The Ways of Science 13
  20. 20. 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 Kepler 4. 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 ofFig. 1.8 Isaac Newton 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. 1.9 Marie Curie 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 Dalton14 High School Science Today I
  21. 21. 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. Fig. 1.11 Albert Einstein 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.Fig. 1.12 Dr. Ricardo Lantican9. 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. 1.13 Dr. Luz Oliveros-Belardo10. 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. The Ways of Science 15
  22. 22. Applying Scientific Attitudes and ACTIVITY 1.7 Values in Your Daily Activities Procedure 1. 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 andtechnology. 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.16 High School Science Today I
  23. 23. 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 andtechnology? Although the different inventions of scientists have improved the quality of life, theyalso brought lots of problems to the society. For instance, gasoline, which fuels engines,pollutes the environment. Refrigerators and air conditioners give off chemicals thatcontribute to the destruction of the ozone layer. The atomic and hydrogen bombs havedestroyed 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 The Ways of Science 17
  24. 24. Procedure 1. 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. Since technology has something to do with problems in the society, it is necessary tohave a deeper understanding of how science and technology work. This will guide you inmaking 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 aregadgets that help us do work easier and faster. This is because of the influence of scienceand technology. Science is a systematized body of knowledge that is developed through observations,researches, and experimentations. Scientists, who are engaged in pure science, do thoroughresearches 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 processedfood and gadgets or devices (computers and sewing machines). Technology also deals withdifferent processes such as fermentation, pasteurization, and cloning. Technology is a science being put to practical use. Take the caseof Thomas Alva Edison, one of America’s most famous inventors. Hisobservation that a thin wire would glow when an electric current passedthrough it, led him to develop the first electric light bulb. The computer is another technological breakthrough that hasa remarkable impact on modern living. Today, computers are usedeverywhere––offices, libraries, schools, banks, malls, and hospitals. They Fig. 1.14 The firstmake work a lot easier, faster, and more precise and accurate. electric light bulb The principles behind the operation of computers have many applications. Forinstance, when you dial a number on the telephone, the telephone system uses a computerto search for that number. Even direct-dial services use computers to enable your telephoneto connect immediately with other telephone networks worldwide.18 High School Science Today I
  25. 25. 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 printedFig. 1.15 ATM on the packages of most products are? They areactually coded messages that tell the name, manufacturer, size,and price of the items in a package. They are called bar codes. Anelectromagnetic device called a scanner enables the computer toread the code on an item and send information about it back tothe computer. The computer then interprets the code and relays Fig. 1.16 A bar code of athe price of the item to the cash register. At the same time, the product being scanned.computer also records that such an item has been bought. Itbecomes 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 inFig. 1.17 The Internet makes certain different parts of the world and to conduct research.tasks easier. In the United States of America, several nonprofit advocacy organizations have teamedup 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 beenmade easier by devices produced by technology. Do the following activity and identify gadgets that make life better. ACTIVITY 1.9 Science, Technology, and Me 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. The Ways of Science 19
  26. 26. Chapter ReviewI. 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 thingsII. Assessing Your Knowledge A. 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.20 High School Science Today I

×