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Science Works! 3 TEXTBOOK

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Page 1: Science works!3 tx_prelims-watermark

Science Works! 3TEXTBOOK

Page 2: Science works!3 tx_prelims-watermark

Science Works! 3Textbook

Philippine Copyright 2012 by DIWA LEARNING SYSTEMS INCAll rights reserved. Printed in the Philippines

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

No part of this publication may be reproduced or transmitted in any form or by any means electronic or mechanical, including photocopying, recording, or any information storage and retrieval systems, without permission in writing from the copyright owner.

Exclusively distributed byDIWA LEARNING SYSTEMS INC4/F SEDCCO 1 Bldg.120 Thailand corner Legazpi StreetsLegaspi Village, 1229 Makati City, PhilippinesTel. No.: (632) 893-8501 * Fax: (632) 817-8700

ISBN 978-971-46-0308-0

AuthorsAntonio V. Coloma is currently studying for his master’s degree in teaching science at EARIST State College (formerly Eulogio “Amang” Rodriguez Institute of Science and Technology). He obtained his bachelor’s degree in secondary education major in general science from Manuel L. Quezon University. He is presently the science coordinator of PAREF Northfield School for Boys in Quezon City.

Claudine F. Guiking obtained her bachelor’s degree in behavioral science from Miriam College in Quezon City. She took up some graduate units in education at the University of the Philippines–Diliman before continuing her master’s degree in education with emphasis on international studies at the Philadelphia Biblical University, Asia Pacific Extension. She has seven years of teaching experience in both preschool and grade school.

Julie Ann M. Miñon received her bachelor’s degree in secondary education major in general science, cum laude, from Philippine Normal University. She is also a licensed teacher. Currently, Ms. Miñon teaches science subjects from grade school to high school at Miriam College.

ReviewerSusan P. Pirante has completed her academic requirements for her master’s degree in teaching science at Mindanao State University (MSU)–Marawi. She finished her bachelor’s degree in science major in biology from MSU–Marawi and her bachelor’s degree in elementary education from Iligan Capitol College. Ms. Pirante is also a registered nurse and a licensed teacher. She has been teaching science subjects for 22 years. At present, she teaches at Ubaldo D. Laya Memorial Central School, Iligan City.

ConsultantAntom V. Revilla finished his master’s degree in biology from Centro Escolar University. He obtained his bachelor’s degree in forestry, cum laude, from the University of the Philippines–Los Baños. Mr. Revilla was a supervisor of Christian Bible Baptist School of Excellence and Development. He taught general science, biology, and scientific research at San Beda College–Manila from 1991–2008. He was also the subject area coordinator of the Natural Science Department of the said college from 2002–2008.

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To the Pupil

Discovery and learning are part of your everyday life. Whether you are playing or studying, you are able to understand and learn about the things around you. This book, Science Works! 3 is meant to teach you different science concepts and skills in an exciting way.

Science Works! 3 will help you to be actively involved in learning concepts about the human body, plants, animals, Earth, sun, and many more. Science concepts and skills are best learned by engaging in activities and performing experiments. These activities will lead you to create your own questions, conduct your own investigations, and develop your own solutions to problems through reasoning and observation.

This book, which has been designed especially for you, includes the following components:

Sci-tionary presents an activity that introduces you to words or terms that you will encounter in the lesson.

Jump Start lists a set of guide questions that are expected to be answered as you go along the lesson.

Feed Your Mind provides the discussion of the science concepts to be learned in the lesson.

Science in Action presents experiments, cooperative learning activities, and individual or group projects that will apply the science concepts you have learned in Feed Your Mind.

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Learning Area Integration relates a particular science lesson to the other subject areas such as English, mathe-matics, and social studies. This will help you appreciate how science is applied to other fields of study.

Rundown lists the important science concepts that should be remembered at the end of each lesson.

Brain Challenge presents 5 to 10-item quiz about the lesson.

Chapter Checkup includes exercises that cover all the topics discussed in a chapter.

Your Move presents an activity that will allow you to apply what you have learned to a real-life situation.

Aside from the components given, some lessons in this book include these additional sections:

Incredible Facts presents interesting or extraordinary facts and trivia related to the science concept.

Proudly Pinoy features notable Filipino people, culture, products, and inventions.

Sci-tainment includes fun games and activities related to the science concept.

Exploring the Web provides links to online activities or exercises that you may access to help reinforce and enrich your learning.

Begin your journey and discovery now! Use what you will learn in this book and apply them to your everyday life.

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Table of Contents

UNIT 1 The Human Body and the Changes of Growing UpChapter 1 The Sense Organs ................................................................................ 2

Lesson 1 The Sense of Seeing ..................................................................................... 2 2 Common Eye Ailments and Their Treatment, and the Proper Care

of the Eyes .................................................................................................. 7 3 The Sense of Hearing .................................................................................13 4 Common Ear Ailments and Their Treatment, and the Proper Care

of the Ears .................................................................................................19 5 The Sense of Smelling ................................................................................24 6 Common Nose Ailments and Their Treatment, and the Proper Care

of the Nose ................................................................................................29 7 The Sense of Tasting ...................................................................................34 8 Common Tongue Ailments and Their Treatment, and the Proper Care

of the Tongue .............................................................................................39 9 The Sense of Feeling ..................................................................................44 10 Common Skin Ailments and Their Treatment, and the Proper Care

of the Skin .................................................................................................49Chapter Checkup ............................................................................................................55

Chapter 2 The Changes of Growing Up .............................................................. 58Lesson 1 Changes in Your Height and Weight ...........................................................58 2 Changes in Your Social and Mental Development .......................................64 3 Healthy Eating Habits ................................................................................68 4 Getting Fit and Relaxed ..............................................................................72 5 Common Diseases That Can Affect You ......................................................77 6 Practicing Good Health Habits ...................................................................81 7 Protecting Yourself from Abuse ..................................................................85Chapter Checkup ............................................................................................................89Your Move ......................................................................................................................91

UNIT 2 Living Things: Plants and AnimalsChapter 3 Plants around You ............................................................................. 94Lesson 1 Parts of Plants ............................................................................................94 2 Classifying Plants .......................................................................................99 3 Where Plants Live ....................................................................................104 4 Growing New Plants ................................................................................110 5 Plants Need Care .....................................................................................115Chapter Checkup ..........................................................................................................120

Chapter 4 Amazing World of Animals ............................................................. 122Lesson 1 Animal Homes .........................................................................................122 2 Animal Groupings Based on the Food They Eat ........................................128 3 Different Body Parts Animals Use ............................................................133

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4 Animal Adaptations .................................................................................139 5 Animals Have Needs ................................................................................145Chapter Checkup ..........................................................................................................150Your Move ....................................................................................................................151

UNIT 3 Matter, Energy, and Force

Chapter 5 Matter around Us ............................................................................ 154Lesson 1 Matter Is Everywhere ..............................................................................154 2 Properties of Materials .............................................................................159 3 Mass and Volume of Matter .....................................................................166 4 Useful and Harmful Materials ..................................................................172Chapter Checkup ..........................................................................................................177

Chapter 6 Light and Energy Sources ................................................................ 179Lesson 1 Sources of Light .......................................................................................179 2 Opaque, Translucent, and Transparent Materials .....................................183 3 Light Bounces and Bends .........................................................................188 4 How Sound Is Made .................................................................................192 5 How Sound Travels ..................................................................................196Chapter Checkup ..........................................................................................................200

Chapter 7 Force and Motion ............................................................................ 201Lesson 1 Force .......................................................................................................201 2 Magnetic Force ........................................................................................205 3 Gravity ....................................................................................................209Chapter Checkup ..........................................................................................................213Your Move ....................................................................................................................215

UNIT 4 Earth, Weather, and Sun

Chapter 8 Soil, Water, and Air ......................................................................... 218Lesson 1 Earth and Its Natural Resources ...............................................................218 2 Soil and Its Uses ......................................................................................223 3 Soil Pollution and Its Prevention ..............................................................230 4 Sources and Uses of Water .......................................................................235 5 Water Pollution and Its Prevention ...........................................................241 6 The Air We Breathe .................................................................................245 7 Air Pollution and Its Prevention ...............................................................249Chapter Checkup ..........................................................................................................253

Chapter 9 Earth’s Weather and the Sun .......................................................... 255Lesson 1 The Weather ............................................................................................255 2 How Weather Affects Us ..........................................................................261 3 Protection from Extreme Weather ............................................................266 4 The Sun ...................................................................................................270 5 Harmful Effects of the Sun .......................................................................273Chapter Checkup ..........................................................................................................277Your Move ....................................................................................................................279

Bibliography .................................................................................................................281

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UNIT1

The picture shows ________________________________________.

Before, I know that ______________________________________________________.

Your body has many parts working together. These body parts help you know the things around you. Your eyes make you see your surroundings. Your ears enable you to hear sounds. Your nose lets you smell odors. Your tongue allows you to taste foods. Your skin helps you feel things. Your eyes, ears, nose, tongue, and skin are your sense organs. In this unit, you will be able to learn about your sense organs—their functions, the common ailments affecting them and their treatments, and the proper ways of caring for them. You will also understand the changes that happen to your body as you grow.

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Science Works! 32

Identify the word(s) being described. Arrange the letters in the box to form the correct word(s). Write your answer on the blank.1. The colored circular part of the eye

r i i s

______________________

2. The dark circle of the eye

l u p i p

______________________

3. The nerve that carries messages to the brain

p t c i o e r v n e

______________________ ______________________

The Sense Organs

The Sense of Seeing

CHAPTER 1

Lesson 1

In this lesson, you will be able to answer the following questions:

1. What are the parts of the eye?2. How does a person see?

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The Human Body and the Changes of Growing Up 3

Look around you. What are the things you see. You can see things because of your eyes. Your eyes are your sense organs for seeing.

Get a mirror and examine your eyes. Look at the colored, round part of your eye, the iris. Irises have different colors. Some people may have green irises, others have blue. Filipinos, like you, usually have black or dark brown iris.

At the center of your eye is the pupil. The pupil is the round opening

at the center of the iris where light passes through. The muscles of the iris control the amount of light passing through the pupil.

Now, notice the part of your eyes that suddenly closes when the light is too bright. This is your eyelids. The eyelids protect your eyes from bright light until your eyes are able to adjust to it. Your eyelids are lined with oil-producing glands found in the inner edge. They keep your eyes moist and clean when you blink.

Do you see the white part of your eyes? It is called the sclera. It protects the inner parts of the eyes and keeps them in correct shape.

This time, carefully observe the clear, bulging surface that covers the front of your eyes. That is the cornea, the part that focuses the light as it makes its way through your eyes.

The parts of the eye that can be seen

eyelid

iris

pupilsclera

eyebrow

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Science Works! 34

Behind the cornea is the aqueous humor, a waterlike fluid that provides oxygen and nutrients to the cornea and the lens.

Through the pupil, light rays enter your eyes. These rays travel through the clear part of the eye located behind the iris. This part is called the lens. It focuses the image on the sensitive part of the retina so you can see things that are near or far.

Exploring the Web Read, watch, and learn! Visit the following Web site to find out more about your sense of sight: http://www.childrensuniver-sity.manchester.ac.uk/interactives/science/brainandsenses/eye .asp (accessed on 05 April 2011). This interactive Web site shows how the eyes work. Test your knowledge by taking the quiz after the lesson.

Lens Test

Objective: Investigate how an eye lens works.

Materials: magnifying lens (to be provided by your teacher), ruler, piece of bond paper, meterstick

The parts of the eye that cannot be seen easily

lens

vitreous humor

retina choroid

optic nerve

aqueous humor

cornea

sclera

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The Human Body and the Changes of Growing Up 5

Procedure:1. Form a group with four members.2. With your group, go to a dim corner of a room with a

window.3. Hold the magnifying lens

about 2 meters (m) from an open window. Use a meterstick to measure how far you are from the window.

4. From the window, position the bond paper on the opposite side of the magnifying lens.

5. Slowly move the paper back and forth until clear images outside the window appear.

Questions:1. How did the image(s) appear on the paper?2. What do you think will happen if the lens of your eye

gets damaged? How will this affect your sight? Why?

The retina receives the light rays from the lens. It is a lining at the back of the eye. The retina has two types of photoreceptor cells: rods and cones.

Rods are responsible for night vision. They also help you see black and white shades.

Cones are responsible for daylight vision. They allow you to see colors in images.

The vitreous humor is a clear, jellylike fluid that fills the space between the lens and the retina. It permits the light to pass through the retina.

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Science Works! 36

The choroid is a layer of blood vessels found between the retina and the sclera. It supplies oxygen and nutrients to the retina.

Each of the receptor cells in the retina senses a part of the image and delivers the message to the brain through the optic nerve, a nerve which connects the eye to the brain. Finally, the brain receives the message and creates an image of the object, which you are then able to perceive.

The eyes are the sense organs for seeing. The eye parts that can be seen are the iris, pupil, eyelids,

and sclera. The eye parts that can only be seen using special

equipment are the aqueous humor, lens, retina, and optic nerve.

Put a check ( ) mark on the blank if the sentence is correct. Put a cross ( ) mark if it is wrong._______ 1. The colored part of the eye is called the iris._______ 2. The pupil protects the eyes from bright light._______ 3. The white part of the eyes is the retina._______ 4. The rods are responsible for daylight vision._______ 5. The aqueous humor is a jellylike fluid that fills the

space between the lens and the retina.

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The Human Body and the Changes of Growing Up 7

Look for the given words in the puzzle. Encircle each word that you will find.

Common Eye Ailments and Their Treatment, and the Proper Care of the Eyes

Lesson 2

e g l a u c o m a p

m l s h w f k y d m

r m t k j g a o n f

z h y p e r o p i a

n b n i o k f i l o

i s c a t a r a c t

f g r x n o m e m d

In this lesson, you will be able to answer the following questions:

1. What are the common eye ailments and their treatment?

2. How can you take proper care of your eyes?

glaucoma cataract sty myopia hyperopia

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Science Works! 38

If you have visited an eye clinic before, you have probably met an optometrist (a person who performs basic eye checkups) or an ophthalmologist (a medical doctor for the eyes). These people help you when you have eye problems or ailments.

The most common eye ailment is an eye infection called conjunctivitis, better known as sore eyes or pinkeye.

A person with conjunctivitis has red, watery, and itchy eyes caused by allergies, bacteria, or viruses. Conjunctivis is contagious, which means it can easily be transferred from one

person to another through direct contact. When you rub your eyes after a hand contact with a person who has conjunctivitis, the germs can be transferred to your eyes. You should immediately inform your parents or elders if you get infected with conjunctivitis.

A person can also experience an infection of the eyelid. It is a red swelling along the edge of an eyelid. This swelling is known as sty (kuliti). Sty is caused by bacteria and therefore may be contagious.

To relieve the pain and speed up the rupture of a sty, apply warm compress to the infected area for about 10 minutes, three times a day or as needed. Never press or squeeze a sty to prevent further infection. Ask your parents or elders to consult a doctor if a sty persists for several days.

Conjunctivitis

Sty

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The Human Body and the Changes of Growing Up 9

Some people have a poor vision. Poor vision happens when light does not focus correctly on the retina. Poor vision is usually a result of a refractive error, an error in the focusing of light by the eyes. There are three types of refractive errors: nearsightedness, farsightedness, and astigmatism.

Nearsightedness or myopia is when a person sees nearby objects clearly, while far objects appear blurred or hazy. This happens when the light that enters the eye focuses on a point in front of the retina.

On the other hand, farsightedness or hyperopia is when a person sees faraway objects clearly, while nearby objects appear to be blurred. This happens when the light that enters the eye focuses on a point behind the retina. Wearing specialized eyeglasses or contact lenses will help a nearsighted or farsighted person see objects more clearly.

Astigmatism is when the eyes are unable to focus light evenly because the cornea of one eye is more curved than the other. As a result, whether an object is near or far, the image produced is always blurred.

Snellen Chart Reading

Objective: Record and compare one’s visual ability with a classmate.

Materials: Snellen chart (to be provided by your teacher), small index card, science notebook

Procedure: 1. Stand approximately 6 m away from the Snellen chart.2. Cover one eye with the index card.3. Read each row of letters in the chart.

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Science Works! 310

Glaucoma

An eye affected by cataract

4. Ask a classmate to record all the letters that you missed or read incorrectly.

5. Repeat steps 2–4 with your other eye.6. Compare your results with your classmate.

Questions:

1. Which row number did you find difficult to read? What letter(s) from this row did you read incorrectly?

2. Did both of your eyes have the same result? Which eye showed more incorrect results?

3. What do you think does the Snellen chart test say about your visual ability?

As people get older, they may experience some eye disorders. Glaucoma is an eye disorder caused by an abnormal pressure exerted by the fluids in the eye. It can cause blindness. Glaucoma can be very hard to detect and doctors estimate that half of the people affected by glaucoma may not know that they have it. There is no cure yet for glaucoma. Doctors usually prescribe eyedrops to control it. Having a regular eye checkup is very important.

Another eye disorder that mostly affects the elderly is cataract. It is caused by the clouding of the lens of the eye. As a person gets older, the old cells in the lens of the eye die. These cells build up over time and form “cloudy areas” in the lens. As a result, these “cloudy areas” block one’s vision and

make things look blurred.

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The Human Body and the Changes of Growing Up 11

The common symptoms of cataract include having blurred vision or double vision, being unable to see well at night, changing eyeglasses frequently, and seeing faded colors. Cataract does not spread from one eye to another, but it can occur on both eyes. The exact cause of cataract is still unknown, but it is firmly connected to smoking, diabetes, and too much exposure to sunlight.

Early symptoms of cataract may be corrected by wearing eyeglasses. Surgery is still the best treatment, in which the damaged lens is replaced with an artificial one. A person should see an eye doctor if the symptoms begin to appear.

Proper Care of the EyesFor you to appreciate the beauty of the things around

you, you need to have a healthy eyesight. Here are some practices for the proper care of your eyes.1. Always read with enough light. Do not read while lying

down or while inside a moving vehicle.2. Rest your eyes when tired. Do not overuse them.3. Do simple eye exercises such as looking up and down,

looking left to right, and rolling your eyeballs clockwise and counterclockwise.

4. Avoid rubbing your eyes with your fingers. 5. Do not look directly at the sun. When you are outside

on a sunny day, wear sunglasses or use an umbrella as protection from the sun’s light.

6. If you are wearing eyeglasses or contact lenses, always keep them clean. Remove your eyeglasses or contact lenses before you sleep. Sleeping with your contact lenses on can cause blindness.

7. Do not hold pointed and sharp objects near your eyes.

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Science Works! 312

8. Eat foods rich in vitamin A such as carrots, squash, milk products, and eggs. Vitamin A is a nutrient that is good for the eyes.

9. Visit an optometrist or an ophthalmologist for a regular eye checkup.

• Some of the common eye ailments are conjunctivitis, sty, glaucoma, and cataract.

• The eyes can also have refractive errors. There are three types of refractive errors: nearsightedness (myopia), farsightedness (hyperopia), and astigmatism.

• People should take proper care of their eyes. Having healthy eyes is important for good eyesight.

Match the eye problems in column A with their descriptions in column B. Write the letter of the correct answer on the blank. A B_____ 1. astigmatism a. difficulty in seeing far objects_____ 2. cataract b. clouding of the lens of the eye_____ 3. glaucoma c. difficulty in seeing nearby objects_____ 4. hyperopia d. caused by an abnormal fluid

pressure exerted by the fluids in the eye

_____ 5. myopia e. one cornea is more curved than the other

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The Human Body and the Changes of Growing Up 13

Complete the crossword puzzle below by writing the missing letters. Use the given clues in the box as your guide.

The Sense of HearingLesson 3

In this lesson, you will be able to answer the following questions:

1. What are the parts of the ears?2. How does a person hear?

3 1

2

4

A

E

W

E R R M

X

N

N

A

TO E R

Down1. The innermost part of the

ear that sends messages to the brain (two words)

3. A waxy substance in the ear

Across2. A thin layer of skin that

vibrates between the outer ear and the middle ear

4. Part of the ear that can easily be seen (two words)

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Science Works! 314

Your ears are your sense organs for hearing. They help you hear sounds.

The human ear is composed of three main parts—the outer ear, the middle ear, and the inner ear.

When you look at your ears in front of a mirror, you can see the outer ear, the part of the ear that is easiest to see. It is cup-shaped and is found on the side of the head. It collects and guides the vibrations or sound waves produced by an object as they travel to the ear. The outer ear is made up of the pinna or auricle and the ear canal.

The pinna or auricle is a curved structure that collects sound waves. The ear canal is a tube that extends from the auricle to the eardrum. It is lined with delicate hairs and glands. These glands produce a waxy substance called cerumen, commonly known as earwax. It protects the ear canal from infection and traps dirt that enters the ear.

The eardrum, also known as tympanic membrane, is a thin piece of skin located at the end of the ear canal. It vibrates when sound waves traveling from the ear canal hit it. The vibrations produced are then carried to the middle ear.

hammer

ear canaleardrum

stirrup

anvil

auditorynerve

cochlea

eustachian tube

outerear

middleear

innerear

pinna

Parts of the ear

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The Human Body and the Changes of Growing Up 15

The middle ear, a hollow chamber filled with air, picks up the sound waves from the outer ear. The middle ear has three very tiny bones—the hammer, the anvil, and the stirrup.

The hammer is located next to the eardrum. The vibrations of the eardrum cause the hammer to vibrate as well. Then the hammer causes the anvil (the tiny middle bone that connects the hammer and the stirrup) to vibrate, which in turn causes the stirrup to move. Finally, the stirrup passes the vibrations to the fluid inside the cochlea. These three tiny bones amplify the sound vibrations and pass them to the inner ear.

The inner ear is a fluid-filled structure which not only contains the organs for hearing but also regulates the sense of balance of the body. The inner ear is made up of three parts—the cochlea, the auditory nerve, and the semicircular canals.

The fluid-filled cochlea is a snail-shaped structure in the inner ear. As the stirrup causes the fluid in the cochlea to vibrate, the hairlike nerve endings called cilia move. The cilia then converts the vibrations into nerve signals which are sent to the brain through the auditory nerve. The auditory nerve carries messages collected

from 25 000 auditory receptors in the ear to the brain. When nerve signals reach the brain, the brain interprets them and tells the sound you hear.

The semicircular canals are the fluid-filled loops near the cochlea that help maintain balance. When you move your head, the fluid moves. It pushes against the hairlike nerve endings that send nerve signals to your brain. From these nerve signals, the brain knows the movements your body is making. Thus, you do not fall or stumble easily while you are playing, walking, or standing.

Cilia lining the cochlea

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Science Works! 316

How You HearHow do you hear your favorite song? When an object,

such as a radio, makes a sound, it sends vibrations through the air. The vibrations then travel to your ear canal and hit the eardrum. These vibrations cause the hammer, anvil, and stirrup in the middle ear to move. As these three bones move, they also cause the fluid inside the cochlea to vibrate. Then, the cilia in the inner ear changes the vibrations into nerve signals which are sent to the brain through the auditory nerve. The brain interprets the signals and tells the sounds you hear.

Exploring the Web Learn more about the parts and function of your ears. Visit http://www.childrensuniversity.manchester.ac.uk/interactives/science/brainandsenses/ear.asp (accessed on 05 April 2011) and take a test about how your ears work.

Let’s Hear It!

Objective: Demonstrate how sound is heard. Materials: metal spoon, kite string (50 centimeters)Procedure:

1. Tie the handle of the metal spoon at the center of the string.

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The Human Body and the Changes of Growing Up 17

• The ears are the sense organs for hearing.• The ears are divided into three main parts—the outer ear,

the middle ear, and the inner ear.• The outer ear is made up of the pinna or auricle and the

ear canal.• The eardrum is a thin piece of skin located between the

outer ear and the middle ear.• The middle ear is made up of three tiny bones—the

hammer, the anvil, and the stirrup.• The inner ear is made up of the cochlea, the auditory

nerve, and the semicircular canal.

2. Wrap the ends of the string gently around both your index fingers. Make sure that the strings are of the same length. Put the tip of your index finger in each ear.

3. Lean over so that the spoon hangs freely. Then tap it against the side of the table.

Questions:1. What happened in the experiment? Were you able to

hear any sound?2. How were you able to hear the sounds?

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Science Works! 318

1

23

5

4

6

A. Label the parts of the ear. Write your answer on the blank.1. _____________

2. _____________

3. _____________

4. _____________

5. _____________

6. _____________

B. Write T on the blank if the sentence is true. If it is false, change the underlined word(s) to make the sentence true._______ 1. The cochlea is lined with tiny hairlike cells

called auditory nerves which carry nerve signals to the brain.

_______ 2. The three small bones in the middle ear are the hammer, anvil, and stirrup.

_______ 3. The eardrum is also called the auricle._______ 4. The snail-shaped structure in the inner ear is

called cochlea._______ 5. Next to the eardrum is the stirrup.

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The Human Body and the Changes of Growing Up 19

Use the code below to form the correct word(s). Replace each number with a letter based on the given code. Write your answer on the blank.

Code:

A B C D E F G H I J K L M2 4 6 8 10 12 14 16 18 20 22 24 26

N O P Q R S T U V W X Y Z1 3 5 7 9 11 13 15 17 19 21 23 25

Common Ear Ailments and Their Treatment, and the Proper Care of the Ears

Lesson 4

1. ________________________________ 13 18 1 1 18 13 15 11 2. ________________________ __________________ 3 13 18 13 18 11 26 10 8 18 2 3. ___________________________ _____________________ 10 21 13 10 9 1 2 24 3 13 18 13 18 11

In this lesson, you will be able to answer the following questions:

1. What are the common ear ailments and their treatment?2. How can you take proper care of your ears?

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Science Works! 320

There are some people who have trouble hearing. Others cannot hear at all. Hearing loss or hearing impairment is a condition where one or both ears have been damaged, causing a person to hear only some sounds or nothing at all. Exposure to loud music and noise for long periods of time is one of the causes of hearing loss.

People with hearing impairments usually use hearing aids to help them hear sounds. Hearing aids are small electronic devices that amplify or increase the loudness of sounds. They can be worn behind the ear or inserted into the ear canal.

Aside from loss of hearing, certain ailments may happen to the ears. What are some of the common ear ailments?

A person may experience hearing ringing or buzzing sounds in the ear. This abnormal hearing of ringing sounds is called tinnitus. It can be a sign of an ear infection or injury caused by very loud sounds. It can also be a side effect of taking oral medications such as aspirin.

One of the most common ear ailments is external otitis, also known as swimmer’s ear. It is usually caused by bacteria or foreign objects trapped in the ear canal. The common symptoms of external otitis are pain and itchiness in the outer ear. The outer ear also becomes swollen and may produce a pus (thick, yellowish fluid) discharge.

External otitis can be prevented by keeping the ears thoroughly dry after swimming or taking a bath. When removing dirt from the ears, use a thin, damp cloth. External otitis can also be treated through proper medication.

Hearing aid

External otitis

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The Human Body and the Changes of Growing Up 21

I Hear a Sound

Objective: Determine the direction of the source of sound.Materials: chair, big handkerchief, pen, paperProcedure:

1. Form a group with five members.2. Place a chair in the middle of a room. Using the

handkerchief, blindfold one member and let him or her sit on the chair. The rest of the members will form a large circle around the blindfolded member.

3. One member in the circle will clap his or her hand twice.

4. The blindfolded member must point to the direction of the source of sound. The other members will record the result in the chart on the next page.

5. After the blindfolded member listens with both ears, he or she will cover his or her right ear and then left ear, and do steps 3 and 4 again.

6. Do steps 2–5 until all members have been blindfolded.

Otitis media (luga) is an ailment affecting the middle ear. Pus builds up behind the ear which causes redness, swelling,

and pain. Otitis media can be treated with medication such as antibiotics (substances that kill harmful bacteria which cause the infection). If not given immediate attention, otitis media can cause hearing impairment and even deafness.

Otitis media

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Put a check ( ) mark in the box if the blindfolded member correctly determined the direction of the source of sound. Otherwise, put a cross ( ) mark.

Member With Both Ears With Right Ear With Left Ear

1

2

3

4

5

Questions:1. Were you able to locate correctly where the sound

came from with two ears or with just one ear?2. How were the results similar or different between the

hearing ability of your right ear and left ear?3. How does having a limited hearing ability affect your

daily life? Give examples.

Proper Care of the EarsTo prevent having ear ailments, it is very important to

keep your ears healthy. Here are some ways on how to take proper care of your ears.1. Clean your ears regularly. Gently remove dirt by using a

clean, damp cloth. 2. Do not put small or sharp objects inside your ears.3. Avoid listening to very loud sounds.4. Always keep your ears dry.5. Avoid swimming in dirty pools or bodies of water. 6. Have your ears examined at least once a year by an ear

doctor specialist.

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The Human Body and the Changes of Growing Up 23

• Α hearing aid is a small electronic device that amplifies or increases the loudness of sounds.

• Tinnitus is an abnormal hearing of ringing sounds.• External otitis or swimmer’s ear is a common ailment

that affects the outer ear.• Otitis media is an ailment that affects the middle ear.• Taking care of the ears can help prevent some ear

ailments.

Match the words in column A with their descriptions in column B. Write the letter of your answer on the blank.

A_____ 1. otitis media_____ 2. hearing aid_____ 3. tinnitus_____ 4. external otitis_____ 5. hearing loss

Ba. also known as swimmer’s earb. abnormal hearing of ringing

soundsc. condition in which both ears

have been damagedd. locally known as lugae. small electronic device used

to amplify sounds

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Identify the word(s) being described. Arrange the letters in the box to form the correct word(s). Write your answer on the blank.

1. The two holes of the nose

s o l r t i n s

______________________

2. The passageway of air entering the nose

l a n s a v t i y c a

_______________ __________________

3. The nerve in the nose that carries messages to the brain

f a c o r t l y o r v e e n

_________________________ _______________

The Sense of SmellingLesson 5

In this lesson, you will be able to answer the following questions:

1. What are the parts of the nose?2. How does a person smell?

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The Human Body and the Changes of Growing Up 25

You smell many things every day. Your nose is your sense organ for smelling. It helps you recognize a pleasant odor such as the smell of perfume and an unpleasant odor like the smell of rotten garbage.

Your nose has two important tasks—to breathe in air and to smell things. Do you know the parts of your nose and their functions?

The nose is divided into two narrow passages by a thin wall of soft bone and cartilage. Air enters through the nostrils (two openings or holes) that lead the air into the nasal cavity (a hollow passageway of air in and out of the nostrils). The nasal cavity is lined with a mucous

membrane that contains tiny hairs, known as cilia, which filter the objects that enter the nose. On top of your nasal cavity are nerve cells, called olfactory receptors, that recognize the scent particles. Then these cells send signals through the olfactory nerve to the brain. The brain then interprets these signals so you can now smell that delicious chicken or avoid that rotten egg.

Parts of the nose

nostrils

nasal cavity

olfactory nerves

cartilagebones

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Your sense of smell affects your daily life. Smelling lets you enjoy eating more because of the aroma of foods. It also helps you detect harm such as preventing you from eating spoiled foods. Smelling is as important as your other senses. Your sense of smell is actually connected to your memory and emotions. For example, the smell of popcorn may remind you of being at a movie house or cinema with your family. The smell of your favorite food can also make you happy.

Exploring the Web Take a quiz about the parts and function of the nose on this Web site: http://kidshealth.org/kid/htbw/_bfs_NOSEquizsource.html (accessed on 05 April 2011).

Intensity of Smell

Objective: Investigate why the intensity of smell changes over time.

Materials: 5 milliliter (mL) cologne, 1 tablespoon coffee granules, 5 mL shampoo, small plastic container with cover

Procedure: 1. Work with a partner for this activity. 2. Place each item in separate containers. Label each

container as 1, 2, and 3.3. Pupil A will open the first container and hold it close

to pupil B’s nose. 4. Pupil B will take one or two sniffs and note the

strength of the smell of the item by encircling the number in the chart on the next page.

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The Human Body and the Changes of Growing Up 27

4. Pupil A will close the container. After 5 seconds, repeat steps 2 and 3 two times using the same container. Pupil B will note the strength of the smell of the item after sniffing it.

5. Do the same procedure for containers 2 and 3.Item Trial 1 Trial 2 Trial 3

CologneStrong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

CoffeeStrong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

ShampooStrong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

Strong Weak

5 4 3 2 1

Questions:1. How would you describe the strength of the smell of

the cologne, coffee, and shampoo at the time when you first sniffed them?

2. How did the strength of the smell change after the second and third trials?

3. Why do you think the strength of the smell changed over time?

• The nose is the sense organ for smelling.• The nose consists of the nostrils, nasal cavity, olfactory

receptors, and olfactory nerve.

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Match the parts of the nose in column A with their descriptions in column B. Write the letter of your answer on the blank.

A B______ 1. cilia a. hollow passageway of air ______ 2. nostrils b. tiny hairs that filter the air______ 3. nasal cavity c. cells that recognize the

scent particles______ 4. olfactory nerve d. nerve in the nose that

carries signals or messages to the brain

______ 5. olfactory receptors e. two openings of the nose where air enters

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Common Nose Ailments and Their Treatment, and the Proper Care of the Nose

Lesson 6

Find the given words in the word puzzle. Encircle each word that you will find.

common cold runny nose nosebleed

n c r h i o l p f n x

o f u a w d e g s c t

s k n b n t y u m h n

e g n o r d s d w c t

b a y g c d y g l i h

l f n t e i p r j l s

e c o m m o n c o l d

e b s f r s y d n l c

d k e m l h o g i b e

In this lesson, you will be able to answer the following questions:

1. What are the common nose ailments and their treatment?

2. How can you take proper care of your nose?

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Look at the picture on the right. What do you think is happening to the child?

Just like the other sense organs, the nose can be affected by many ailments. What are these ailments?

When you are sneezing a lot and you have a sore throat, cough, and fever, you probably have a common cold. This ailment affects the nose. It is caused by a virus (tiny germs that carry illnesses) that can spread in the air through sneezing and coughing. A virus can also be transferred from one person to another through saliva or mucus (a sticky discharge coming from the nose).

To prevent yourself from having a cold, avoid contact with someone who has it. Wash your hands before eating or touching your face. Washing your hands thoroughly kills germs. If you happen to have a cold, get plenty of rest, drink plenty of fluids that are rich in vitamin C, and gargle a glass of warm water with salt. Avoid spreading the virus. Use a handkechief or a tissue when you sneeze. Make sure to cover your mouth when you cough, too.

Runny nose occurs when the nasal passages become swollen due to an irregular discharge of mucus. Runny nose can be caused by a cold, influenza or flu, allergies to dust or pollen, and irritants like cigarette smoke or perfume. When you have a runny nose, you might have trouble breathing because of the presence of mucus. Blow your nose gently using a clean tissue or towel. Drink plenty of water to help thin the mucus. You may also use nasal sprays prescribed by a doctor.

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The Human Body and the Changes of Growing Up 31

Rhinitis is the swelling of the nasal cavity caused by airborne irritants or allergens. The most common allergens are pollen, dust mites, molds, and animal dander (hair, feather, or skin particles). Symptoms of allergic rhinitis include repetitive sneezing, nasal congestion, runny nose, itchy eyes and nose, and sore throat. The best treatment for this ailment is to avoid contact with allergens. Taking medication such as antihistamines and decongestants may help, but it is best to consult a nose specialist for a checkup.

Sinusitis is the swelling of the sinuses (air-filled chambers in the skull around the nose) caused by viruses, fungi (molds), and allergies. Symptoms of sinusitis include nasal obstruction, fever, headache, facial pain or pressure, sore throat, fatigue, pain in the upper teeth, and bad breath.

A nosebleed usually occurs when the lining in the nose becomes really dry due to dry weather. Constant picking of

the nose and blowing it very hard can also cause nosebleed. To stop the nose from bleeding, stay calm, sit down, and lean

forward. Then gently pinch the area along your nostrils and the bridge of your nose.

Hold that position for five minutes. Another way to stop nosebleed is to apply ice pack or cold compress on your nose. When the bleeding stops, do not bend and avoid blowing out any of the blood remaining in

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the nostrils to prevent another nosebleed. Taking vitamins and minerals such as vitamin A, zinc, and iron can also help prevent nosebleed.

Proper Care of the NoseThe nose can be easily affected with different allergens

and pollutants. Therefore, it is important to keep it clean and healthy. Here are some ways to take proper care of the nose.

1. Cover your nose when you smell a foul odor.

2. Avoid blowing your nose very hard.

The Tale of the Ailing NoseObjective: Create a storybook to describe the signs of

common nose ailments.Materials: pencil, different art materials, pieces of bond

paperProcedure:

1. Work with a partner for this activity. 2. Choose one ailment affecting the nose.

3. Do not put anything inside your nose.

4. Clean your nose regularly and gently by using a clean and moist cloth.

5. Visit a doctor if you experience something painful in your nose.

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The Human Body and the Changes of Growing Up 33

3. Research in the library or the Internet about this ailment.4. Create a storybook that will tell a story to children about

this ailment. Make it attractive and interesting. 5. Include in your storybook the causes, symptoms, and

treatment of this nose ailment, and the good habits children should practice to keep them from having this ailment.

6. Be ready to share your storybook with the class.

• The common nose ailments include common cold, runny nose, rhinitis, sinusitis, and nosebleed.

• The nose can be affected by certain ailments. It is important to keep it clean and healthy.

Match the descriptions in column A with the nose ailments in column B. Write the letter of your answer on the blank.

A_____ 1. occurs when there is an

irregular discharge of mucus_____ 2. the swelling of the sinuses_____ 3. caused by a virus_____ 4. the swelling of the nasal cavity_____ 5. occurs when the lining of the

nose becomes dry

Ba. common coldb. runny nosec. rhinitisd. sinusitise. nosebleed

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The Sense of TastingLesson 7

Look for the given words in the word puzzle. Encircle each word that you will find.

sweet salty bitter sour umami

y s b i t t e r s

f o s w e e t u x

c u g y b x h l u

e r d h e r i s r

u p s a l t y g t

k u m a m i p s m

In this lesson, you will be able to answer the following questions:

1. What are the five kinds of tastes?2. How does the tongue work?

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The Human Body and the Changes of Growing Up 35

tongue

Get a mirror and open your mouth. What do you see? Your tongue is your sense organ for tasting. It is a strong, movable muscle that you use for tasting food. Aside from tasting food, the tongue also plays other important roles—to help you chew, to help you swallow, and to let you pronounce letters or words.

How does your tongue work? Observe your tongue again. Do you see the “bumps”

on the upper surface of your tongue? These tiny bumps are called papillae (singular, papilla). The papillae contain your taste buds. Your tongue and the roof of your mouth are covered with thousands of taste buds. Also arranged among the taste buds are taste receptors which help you identify the different flavors of foods.

The taste buds can identify five kinds of tastes. These are sweet, salty, sour, bitter, and umami (meaty taste). When you eat food, your saliva helps break down the food into smaller

pieces. The taste receptors located in your taste buds send messages to your brain through the sensory nerve. Then, your brain tells you the taste of the food you are eating.

The tongue

taste buds

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Free Taste

Objective: Group foods by using the sense of taste.Materials: big handkerchief, marshmallows, mangoes,

slice of cheese, oranges, cocoa powder, sugar, coffee, salt, calamansi extract, soy sauce, vinegar, medicine dropper, spoons, small plastic containers

Procedure: 1. Form a group with five members. Take turns in

tasting five varied flavors of food or liquid samples. (Note: Do not taste food that you are allergic to.)2. Begin by collecting and preparing all the food or

liquid samples you are going to use. 3. Blindfold a member of your group and let him or her

taste a food or liquid sample. Use the medicine dropper for the liquid samples.

4. Ask the member to pinch his or her nose as you place a food or liquid sample on his or her tongue. Ask him or her to name the food sample. Record the results in the table on the next page.

Incredible Facts As you grow, your taste buds begin to disappear from the sides and the roof of your mouth, leaving taste buds mostly on your tongue. Some of your taste buds become less sensitive. Others may not even work anymore.

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The Human Body and the Changes of Growing Up 37

5. Repeat steps 3 and 4 for the rest of the group members.

6. Remember that when choosing the food and liquid samples, select a variety of sweet, salty, sour, bitter, and umami flavors.

7. Complete the food tasting chart below.

Sample TasteName of the

FoodCorrect

(yes or no)1

2

3

4

5

Questions:1. What have you noticed when you tasted the food and

liquid samples with a blindfold on? Did they taste better or not?

2. What happened when you pinched your nose? Did you lose your sense of taste?

• The tongue is the sense organ for tasting.• The papillae contain the taste buds that have taste

receptors to identify different tastes.• The five kinds of tastes are sweet, salty, sour, bitter, and

umami.

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A. Put a check ( ) mark on the blank if the sentence is correct. Put a cross ( ) mark if it is wrong.________ 1. The “bumps” on the upper surface of the

tongue are called papillae.________ 2. Umami taste is found in salt and coffee.________ 3. Saliva helps break down food into smaller

pieces.________ 4. Your taste buds are found inside the

papillae.________ 5. The tongue is a strong immovable muscle.

B. Answer the following questions. Write your answer on the blanks. 1. What is your favorite food? Describe its taste.

__________________________________________________________________________________________________

2. Why is your tongue important?__________________________________________________________________________________________________

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Common Tongue Ailments and Their Treatment, and the Proper Care of the Tongue

Lesson 8

Use the code below to form the correct word(s). Replace each number with a letter based on the given code. Write your answer on the blank.

Code:

A B C D E F G H I J K L M7 16 14 23 2 12 25 15 21 11 8 17 4

N O P Q R S T U V W X Y Z5 26 3 20 22 1 24 13 6 18 9 19 10

1. _______________________________ 26 22 7 17 24 15 22 13 1 15

2. ________________________________________________ 1 24 22 7 18 16 2 22 22 19 24 26 5 25 13 2

3. _________________________________________________ 16 17 7 14 8 15 7 21 22 19 24 26 5 25 13 2

In this lesson, you will be able to answer the following questions:

1. What are the common tongue ailments and their treatment?

2. How can you take proper care of your tongue?

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You use your tongue constantly. This is why it is more likely to experience some ailments if you do not take care of it.

A tongue may suffer from sores, or what we commonly know as singaw. Some sores may tell more serious health problems such as allergies and tuberculosis. A person with a tongue sore usually experiences swelling of the tongue or a burning sensation on his or her tongue, resulting to loss of appetite and even fever. The pain and discomfort felt will cause difficulty in chewing, drinking, and swallowing. If you have a tongue sore, gargle water with salt in it. If the sore lasts long, go to a doctor for a checkup.

The color of the tongue can be related to other diseases that a person might be suffering. A healthy tongue is usually pink and covered with papillae. However, a normally pink tongue may become discolored. If the person has a pale, smooth and swollen tongue, he or she may have iron-deficiency anemia.

The tongue can also suffer from an oral thrush or candidiasis. Oral thrush is an infection of the mouth and tongue caused by a fungus (a harmful organism). A person who suffers from oral thrush will have white spots on his or her tongue. These white spots can be painful and may bleed slightly

when scraped or irritated. This ailment is more likely to occur among infants and people wearing dentures or false teeth. Taking antifungal medications prescribed by a dentist or a medical doctor will help stop the infection.

Oral thrush

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The Human Body and the Changes of Growing Up 41

When a tongue becomes swollen and turns to a darker shade of red, a person may have a strawberry tongue. People with a red tongue usually develop enlarged taste buds that appear similar to the dots on a strawberry. Vitamin deficiency and scarlet fever are possible causes of strawberry tongue. Consult a

doctor immediately if your tongue looks red.Have you seen a person with a black,

hairy tongue? Black hairy tongue is caused by too much bacteria growth in the mouth. It occurs when the papillae grow longer than usual, making the tongue look “hairy.” The overgrown papillae get stained with food and collect bacteria, making the tongue look dark or black. This ailment is most likely to occur in people who have poor oral hygiene. People who are taking antibiotics or receiving chemotherapy, and those with diabetes may also be more likely to have a black hairy tongue. Practicing good oral hygiene such as gently brushing the teeth and tongue regularly is the best way to treat black hairy tongue. You should also consult a doctor or a dentist for proper medication.

Proper Care of the TongueKeeping your tongue clean and healthy is very important.

Here are some practices on how to take proper care of your tongue.1. Using a tongue scraper, scrape your tongue gently after

brushing your teeth.

Black hairy tongue

Strawberry tongue

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2. Chew your food slowly to avoid biting your tongue.3. Do not eat foods or drink liquids that are too hot or too

cold.4. Gargle with a mild mouthwash after brushing your teeth

and scraping your tongue.5. Visit a dentist regularly.

Caring for Your Tongue

Objective: Create a brochure to describe the signs of common tongue ailments.

Materials: bond paper, colored pens, markers, pencil, art materials

Procedure: 1. Work with a partner for this activity. 2. Choose a tongue ailment.3. Research in the library or the Internet about your

chosen ailment.4. Design a brochure that will inform people about this

tongue ailment.5. Provide drawings or pictures to illustrate the tongue

ailment.6. Include in your brochure the causes, symptoms, and

treatment of the tongue ailment, and the healthy practices that will prevent people from having this ailment.

7. Be ready to show your brochure to the class.

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• The tongue can be affected by certain ailments.• Tongue ailments can be avoided through proper oral

hygiene. • Tongue sore (singaw), oral thrush, strawberry tongue,

and black hairy tongue are some ailments affecting the tongue.

Write T on the blank if the sentence is true and F if it is false.

_____ 1. Having white spots on the tongue tells that a person has a strawberry tongue.

_____ 2. Practicing good oral hygiene is the best way to prevent tongue ailments.

_____ 3. Discoloration in the tongue may tell other diseases a person might be suffering.

_____ 4. Oral thrush commonly affects adults._____ 5. Slowly chew your food to avoid tongue

ailments.

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The Sense of FeelingLesson 9

Identify the word being described. Arrange the letters in the box to form the correct word. Write your answer on the blank.1. The sense organ of touch

k n i s

______________________

2. The uppermost layer of the skin

p e d i s e m i r

______________________

3. The thickest layer of the skin

m r i s d e

______________________

In this lesson, you will be able to answer the following questions:

1. What are the three layers of the skin?2. Why is your skin important?

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The Human Body and the Changes of Growing Up 45

The skin is the largest sense organ. It is found all over your body. Your skin protects your muscles and internal organs. It also prevents germs and dirt from getting inside your body.

The skin is made up of three layers—the epidermis, the dermis, and the subcutaneous fatty tissue.

The topmost layer of the skin that you can see is the epidermis. On top of the epidermis is a layer of dead skin cells that constantly shed and are replaced by a new layer of skin cells. The nails that protect the tip of your fingers and toes are actually hardened and thickened epidermis.

The dermis is the thickest layer of the skin. It lies underneath the epidermis. The dermis is filled with many tiny nerve endings, which give you information about the things that your body comes in contact with. These nerve endings carry the information to the brain through the spinal cord.

A magnified image of dead skin cells on the epidermis

epidermis

dermis

subcutaneousfatty tissue

Layers of the skin

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The dermis contains nerves, blood vessels, root hairs, sweat glands, and oil glands. Sweat glands regulate your body temperature. Sweat comes out of your body through the pores (tiny holes in the skin). Sebaceous glands are glands that produce an oily substance called sebum, which is the skin’s natural oil.

Your hair grows from the dermis. It can be found on your entire body, except on your palms, lips, and soles of your feet.

The subcutaneous fatty tissue is the innermost layer of the skin. It is mainly made up of fats, which help keep the body warm and absorb shock.

The nerve endings, also known as skin receptors, can tell you if something is hot or cold, soft or hard, rough or smooth, and wet or dry. Your body has about 20 different types of skin receptors that all send messages to the brain. The most common skin receptors are those that detect heat or cold, pain, and pressure.

Touchy-Feely Double Trouble

Objective: Use the sense of touch to identify objects.Materials: 2 marbles, 2 pieces of sand paper, 2 paper clips,

2 balls, 2 bottle caps, 2 paper bags

Incredible Facts Your skin is very sensitive. But not all areas of the skin have equal sensitivity. The most sensitive areas of the skin are those on the hands, lips, face, neck, fingertips, and feet.

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The Human Body and the Changes of Growing Up 47

Language

Soft, hard, smooth, rough, slippery, wet, dry, hot, and cold are words used to describe how things feel to the touch. These words are called adjectives. Adjectives are words that describe people, places, and things. How will you describe the following things: ice cream, towel, mirror, pillow, and apple?

Procedure:1. Work with a partner for this activity. 2. Place one marble, sand paper, paper clip, ball, and

bottle cap in a paper bag. Then put the remaining items in another paper bag.

3. You should have one set of objects in one paper bag and the matching objects in the other bag.

4. Without looking, reach inside the first paper bag for an object and find its pair in the other paper bag.

5. Take turns in picking out pairs of objects in the bags.

Questions:1. What helped you match the objects in the paper bags

even without looking at them? 2. Were some objects difficult to match? Why?

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• The skin is the sense organ for feeling.• The skin is made up of three layers—the epidermis, the

dermis, and the subcutaneous fatty tissue.• The skin has nerves, blood vessels, root hairs, sweat

glands, and oil glands.

Match the words in column A with their descriptions in column B. Write the letter of your answer on the blank.

A_____ 1. subcutaneous

fatty tissue_____ 2. pores_____ 3. epidermis_____ 4. dermis_____ 5. sebum

Ba. thickest layer of the skin b. topmost layer of the skinc. the skin’s natural oild. innermost layer of the skine. tiny holes in the skin

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Common Skin Ailments and Their Treatment,and the Proper Care of the Skin

Lesson 10

Complete the crossword puzzle below by writing the missing letters. Use the given clues in the box as your guide.

1 4

2 3

Across2. An infection caused by

mites

In this lesson, you will be able to answer the following questions:

1. What are the common skin ailments and their treatment?

2. How can you take proper care of your skin?

C

Down1. The growth of pimples,

blackheads, and whiteheads

3. A pus-filled swelling on the skin

4. A very dry skin covered with scales

E

B

L

I S

P

R

A

S

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The skin protects the body. Because it is exposed, it can be affected with different ailments.

Have you experienced having a blister, a corn, or a callus? A blister is a small fluid-filled lump on the surface of the skin. It can be caused by contact with very hot objects or it can be an allergic reaction to insect bites. A corn is a thickened part of the skin caused by too much pressure. It is usually found on the side of toes. A callus is a patch of hard skin usually found on the palms and on the soles of the feet.

Acne is the most common skin disease that affects adolescents and young adults. This is characterized by the growth of pimples, blackheads, and whiteheads on the skin. It starts when the pores in the skin become clogged with sebum. Acne commonly occurs on the face.

Boil, locally known as pigsa, is an infected, pus-filled swelling on the skin that starts in a hair follicle or oil gland. Most boils are caused by a germ that enters the body through a tiny opening in the skin. The most common areas for boils

to appear are on the face, neck, armpits, shoulders, and buttocks. One of the ways to ease the pain and help draw the pus out is to apply a warm, moist compress on the affected area. Wash the boil with an antibacterial soap, apply an ointment, and cover it with a bandage. If an infected person experiences high fever and chills, he or she should immediately see a doctor.

Acne

Boil (pigsa)

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Psoriasis is a noncontagious skin ailment that causes redness and dryness of the skin. The dry skin is covered with scales or flakes usually found on the elbows, knees, and scalp. A person with psoriasis is likely uncomfortable because of itchiness of the skin. There is no cure for psoriasis, but doctors prescribe ointments to help ease the itchiness.

Have you experienced getting a sunburn? Sunburn is the reddening of the skin caused by too much exposure to sunlight. Peeling of the skin usually follows several days later. To protect your skin, limit your sun exposure between 10:00AM to 3:00 PM. During these times, the light coming from the sun is most intense. Apply sunscreen on your skin to avoid getting sunburned.

Incredible Facts There are some people who are very sensitive to sunlight. When exposed to sunlight, they experience itchiness and painful skin redness, and swelling. They may even get blisters. This skin condition is a type of cutaneous porphyria, also known as “vampire disease.”

Prickly heat or bungang-araw is an itchy, red rash on the skin. It usually occurs when a person sweats more than usual. The trapped sweat causes irritation and discomfort. A person with prickly heat should keep his or her skin cool and dry. Applying powder, calamine lotion, or antihistamine cream on the affected area also helps.

Prickly heat (bungang- araw)

Psoriasis

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Scabies or galis is an itchy, highly contagious skin infection caused by mites that burrow into the skin. Avoid contact with a person who has scabies. Get medical help immediately once infected.

Tinea versicolor or an-an is a skin ailment that causes the affected skin to change color and become either lighter or darker than

the surrounding skin. It is usually found on the skin covering the shoulder, back, and chest. Antifungal creams can be used to stop the quick spread of this ailment.

Atopic eczema or dermatitis refers to the inflammation of the skin that makes it reddish, itchy, dry, and scaly. It is a chronic (long lasting)

ailment that often develops other allergic conditions such as asthma and high fever. Prescibed creams and ointments can be applied to the affected area to control the itching.

Athlete’s foot or alipunga is caused by a fungus that develops in the moist areas between the toes and parts of the foot. It can spread from one person to another. A person with athlete’s foot can experience scaling, flaking, and itching in the affected area. It is important to keep your feet dry and cool to avoid getting athlete’s foot.

Scabies (galis aso)

Tinea versicolor (an-an)

Athlete’s foot (alipunga)

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Proper Care of Your SkinThe best way to take care of your skin is to keep it clean

all the time. Practicing proper hygiene prevents skin ailments. Here are some ways of caring for your skin.1. Take a bath every day. Use clean water and a mild soap.2. Always wear clean clothes.3. Use an umbrella, apply sunscreen, and

wear protective sunglasses when doing outdoor activities.

4. Drink lots of water every day.5. Take enough rest and sleep.6. Eat foods rich in vitamins and minerals.7. Exercise regularly.8. Avoid using another person’s personal things such as

towel, comb, and handkerchief.9. Consult a dermatologist (a skin doctor) if you have

recurring or long-lasting skin problems.

Skin Problems and Proper Care of the Skin

Objective: Create a poster that informs people about a skin ailment and how to treat it.

Materials: white cartolina, colored markers, pencil, crayonsProcedure:

1. Form a group with four members. 2. Choose one skin ailment and make a poster about it.3. Include information about the skin ailment, its

symptoms, causes, and treatment. 4. Go to the library for additional resources. You may

also use the Internet.

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5. Discuss among your group mates how you can come up with a creative design for your poster.

6. Include appropriate photos or drawings in your poster.

7. Make the poster informative and attractive.8. Display your poster in your school hallway.

• The common skin ailments include acne, boil, psoriasis, sunburn, prickly heat, scabies, tinea versicolor, atopic dermatitis, and athlete’s foot.

• Proper hygiene and healthy habits are important to keep the skin healthy.

A. Match the skin ailments in column A with their descriptions in column B. Write the letter of your answer on the blank. A B______ 1. acne a. itchy, red rash on the skin ______ 2. boil b. results from overexposure to

sunlight______ 3. sunburn c. infected pus-filled swelling on

the skin______ 4. athlete’s foot d. fungal infection on the foot______ 5. prickly heat e. characterized by pimples,

blackheads, and whiteheads

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The Human Body and the Changes of Growing Up 55

A. Encircle the letter of the correct answer.1. Which part of the eye focuses light?

a. cornea b. iris c. lensd. pupil

2. What do you call the curved structure in the ear that collects sound waves from the air?a. anvil b. cochlea c. eardrumd. pinna

3. Which part of the nose serves as a passageway of air?a. nostril b. nasal cavity c. olfactory nerved. olfactory receptor

B. Put a check ( ) mark on the blank if the sentence tells a way of taking proper care of the skin. Put a cross ( ) mark if it does not.______ 1. Use your own towel always.______ 2. Wear the same shirt for several days.______ 3. Exercise regularly.______ 4. Wash your face using a mild soap and clean

water.______ 5. Play outside under the heat of the sun.

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4. What do you call the “bumps” on your tongue?a. sclera b. cone c. papillaed. rod

5. What is the thickest layer of the skin?a. dermis b. epidermis c. sweat glandd. subcutaneous fatty tissue

B. Match the ailments in A with the sense organs that they affect in B. Write the number of your answer inside the correct box in B. A B

1 – rhinitis

2 – cataract

3 – psoriasis

4 – candidiasis

5 – otitis media

eyes ear

nose tongue

skin

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The Human Body and the Changes of Growing Up 57

1. 2.

3. 4.

5.

C. Check ( ) the pictures that show proper care of the sense organs.