2. Science Works! 2
Textbook
Philippine Copyright 2012 by DIWA LEARNING SYSTEMS INC
All 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,
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from the copyright owner.
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DIWA LEARNING SYSTEMS INC
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ISBN 978-971-46-0306-6
Author
Claudine F. Guiking has a 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.
Consultant
Antom 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 has 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.
3. 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! 2, is meant to teach you different science concepts and
skills in an exciting way.
Science Works! 2 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.
4. Learning Area Integration relates a particular
science lesson to the other subject areas such as English,
mathematics, 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 above, 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.
5. Table of Contents
UNIT 1 The Human Body
Chapter 1 Exploring Your Senses …………………………………………………. ..... 2
Lesson 1 Discovery through Your Senses ………………………………………….. ....... 2
2 Exploring the Sense of Sight ..............................................................9
3 Exploring the Sense of Hearing ........................................................ 14
4 Exploring the Sense of Smell …………………………………………… ........ 19
5 Exploring the Sense of Taste ……………………………………………......... 23
6 Exploring the Sense of Touch ………………………………………….. ........ 27
7 The Sense Organs Work Together ……………………………………... ...... 33
8 Caring for Your Sense Organs ......................................................... 37
Chapter Checkup ............................................................................................... 42
Chapter 2 Knowing Your Body ................................................................. 46
Lesson 1 The Foods the Body Needs .............................................................. 46
2 Growth and Change ......................................................................... 51
3 Similarities and Differences among Children.................................... 56
4 Keeping Yourself Healthy and Strong ............................................... 61
Chapter Checkup ................................................................................................ 65
Your Move ....................................................................................................... 67
UNIT 2 Plants and Animals
Chapter 3 Discovering Plants ................................................................... 70
Lesson 1 Parts of Plants ................................................................................ 70
2 Groups of Plants ............................................................................. 75
3 Different Plant Habitats .................................................................. 80
4 How Plants Reproduce ................................................................... 84
5 Needs of Plants ............................................................................... 89
6 Uses of Plants ................................................................................. 93
Chapter Checkup ............................................................................................... 98
Chapter 4 Understanding Animals ..........................................................100
Lesson 1 Kinds of Animals ........................................................................... 100
2 How Animals Move ....................................................................... 105
3 What Animals Eat ......................................................................... 110
4 How Animals Reproduce .............................................................. 115
5 How Animals Adapt to Their Environment ................................... 119
6 How People Can Protect Animals .................................................. 125
6. Chapter Checkup ............................................................................................. 130
Your Move ..................................................................................................... 131
Unit 3 Matter and Energy
Chapter 5 Exploring Matter ................................................................... 134
Lesson 1 Understanding Matter ................................................................... 134
2 Properties of Solids ........................................................................ 138
3 Properties of Liquids ..................................................................... 142
4 Properties of Gas .......................................................................... 145
5 Using Matter at Home ................................................................... 148
Chapter Checkup ............................................................................................. 152
Chapter 6 Discovering Energy and Force ................................................ 155
Lesson 1 Forms of Energy ............................................................................ 155
2 How Light Travels ......................................................................... 159
3 Sources of Heat.............................................................................. 164
4 How Sounds Are Produced ............................................................ 168
5 Electricity ..................................................................................... 173
6 The Force of Magnets ................................................................... 177
Chapter Checkup ............................................................................................. 180
Your Move ..................................................................................................... 183
Unit 4 Earth and Space
Chapter 7 Exploring Planet Earth ......................................................... 186
Lesson 1 Earth, Our Home .......................................................................... 186
2 Landforms .................................................................................... 191
3 Bodies of Water ............................................................................ 197
4 Earth’s Natural Resources ............................................................. 202
5 Kinds of Weather .......................................................................... 208
6 Elements of Weather .................................................................... 213
7 Caring for Earth ............................................................................ 219
Chapter Checkup ........................................................................................... 224
Chapter 8 Exploring the Solar System ................................................... 226
Lesson 1 The Sun and Earth’s Movement .................................................... 226
2 Phases of the Moon ...................................................................... 232
3 Planets ......................................................................................... 237
4 Other Objects in the Solar System ................................................. 242
Chapter Checkup ............................................................................................. 246
Your Move ..................................................................................................... 247
7. 1UNIT
The pictures show _________________________________________.
Before, I know that ________________________________________.
H ow do you know about the things around you? Why can
you enjoy them? What makes it possible for your body
to do several things at the same time?
Your body works in amazing ways. It allows you to
explore and discover the world. In this unit, you will learn
more about your body. Find out how wonderfully made you
are.
8. CHAPTER 1
Exploring Your Senses
Lesson 1 Discovery through Your Senses
Find the correct words to complete the sentences. Write
in the boxes the letters that match the given numbers. Use the
given code below.
Code:
1 2 3 4 5 6 7 8 9 10 11 12 13
A B C D E F G H I J K L M
14 15 16 17 18 19 20 21 22 23 24 25 26
N O P Q R S T U V W X Y Z
1. People learn about their surroundings through their
.
19 5 14 19 5 19
2. The
19 5 14 19 5 15 18 7 1 14 19
include the eyes, ears, nose, tongue, and skin. They
receive messages from the surroundings and send them to
the brain.
3.
14 5 18 22 5 18 5 3 5 16 20 15 18 19
send information to the brain.
2 Science Works! 2
9. In this lesson, you will be able to answer the following
questions:
1. What are the five senses and five sense organs?
2. What can your senses tell you about your
surroundings?
3. How do the sense organs send messages to the brain?
4. Why are the five senses important?
eye
ear
The sense organs are parts of your nose
body that you use to understand the mouth
things around you. You use them to
see, hear, smell, taste, and touch (feel).
You can also sense changes in your skin
surroundings. This is because each
sense organ has nerve receptors. These
receptors send messages or information
to your brain. Your brain then tells you
what you are seeing, hearing, smelling,
tasting, or touching (feeling). It tells you
how to respond to things around you.
For example, if you accidentally touch something hot, the
receptors in your hand send a message to your brain. You
instantly pull away your hand so you will not burn it.
There are five main sense organs: eyes, ears, nose,
tongue, and skin.
Your eyes allow you to see things. They can help you
identify colors, sizes, and shapes of objects. You can sense
The Human Body 3
10. light, movement, and position of objects using your eyes. This
way, you do not bump into objects.
Your ears allow you to hear music, voices of people
talking, alarms, and many other sounds. You use them to tell
if a sound is loud or soft.
Your nose allows you to detect scents and recognize the
odor of things around you. Flowers, perfumes, popcorn, and
freshly baked cookies smell good. The smoke coming from
vehicles, and the odor of clogged canals and spoiled food
smell bad.
Your tongue helps you taste and identify the different
flavors of what you eat or drink. There are different kinds of
tastes: sweet, sour, salty, bitter, and umami.
A cake tastes A lemon tastes Patis tastes Ampalaya tastes Cheese tastes
sweet. sour. salty. bitter. umami.
The skin all over your body allows you to feel the
textures of objects. Imagine that you are walking along the
beach on a hot day. The gentle wind is blowing on your face.
You can feel the grainy hot sand on your feet. You can feel the
cold ice cream in your mouth. You can touch the rough sides
of the ice cream cone with your fingertips.
You use your sense organs to explore and understand
your surroundings. You can enjoy delicious food, the sound
of music, and the fragrance and colors of a flower because of
your senses. You can know and respond to changes around
you through your senses. For example, by smelling spoiled
milk, you know that it is not safe to drink it anymore.
4 Science Works! 2
11. Using My Sense Organs
Objectives: 1. Identify the five senses.
2. Use the senses to observe and describe given
objects.
3. Classify and group given objects through a
chart.
4. Enumerate ways in which the five senses
help in performing daily activities.
Materials: two paper plates, two fruits
Procedure:
1. Observe each fruit. Describe its color, size, shape,
and texture.
2. Write the descriptions in the given table.
Characteristics Fruit 1 Fruit 2
Color
Shape
Size
Texture
3. Look at your list of characteristics in the table above.
Group the characteristics according to the senses you
used to observe them.
Sense Sense Sense Sense
Sense of
of of of of
Hearing
Sight Smell Taste Touch
Fruit 1
Fruit 2
The Human Body 5
12. Language
Look at the words you wrote to describe the fruits. They
describe how the fruits look, feel, taste, and smell. These words
are called adjectives. Use adjectives to describe other objects
around you.
You learn about the world through your five senses. The
five senses are sight, hearing, smell, taste, and touch
(feel).
Sense organs have nerve receptors that send messages to
the brain.
You see with your eyes. You can tell the colors, shapes,
and sizes of objects.
You hear sounds with your ears. You can tell if sounds are
loud or soft.
You smell with your nose. You can identify different
odors.
You taste with your tongue. You can tell if a food is sweet,
salty, sour, bitter, or umami.
You touch (feel) with your skin. You can tell if an object is
hot, cold, soft, hard, rough, or smooth.
6 Science Works! 2
13. A. Complete each sentence. Choose the correct answer from
the words in the box.
sense organs hearing nose
nerve receptors smell taste
1. Your ___________________ include your eyes, ears,
nose, tongue, and skin.
2. Your sense of _______________ tells you if a sound is
loud or soft.
3. You can tell the flavor of food with your sense of
_______________.
4. Your nose helps you ________________ good and bad
odors.
5. Sense organs have ________________ that send
messages to your brain.
The Human Body 7
14. B. Circle the object that you can describe or name using the
given sense organ.
tongue
eyes
skin
nose
ears
8 Science Works! 2
15. Lesson 2 Exploring the Sense of Sight
The following list of words are the parts of the eye. Look
for these words in the puzzle and circle them.
1. lens O F Y Z X S L Y X Q
2. iris P M G J J L E J L L
3. retina T U G K A A N E G T
4. pupil E N P B N Q S R K I
R D E I R I S E V I
N Y T N L B V T N L
C E A A A I H A S T
V X K G I U G L P T
P H B Y I A K L V D
U R E T I N A D O W
In this lesson, you will be able to answer the following
questions:
1. What are the parts of the eye?
2. How do your eyes help you see?
3. What are some conditions that affect one’s eyesight?
4. Why is your sense of sight important?
The Human Body 9
16. The eye is the sense organ for seeing. With your eyes, you
can see shapes, colors, and sizes of objects. You can find light
and tell direction and distance.
cornea
optic nerve
pupil vitreous
(opening) lens
gel
retina
iris pupil
iris
ciliary body
The eye has many parts that help you see. The iris is
the colored part of the eye. The opening in the center of the
eye through which light goes in is the pupil. It controls the
amount of light that enters the eye. The light that passes
through the pupil will then strike the lens. The lens focuses
the light rays to the retina, the lining of the inner eye. The
retina detects images and colors of objects. These images are
turned into signals that are sent to the brain. The brain then
tells you what you are seeing.
Some people cannot see things well because they have
vision or eyesight problems. Nearsightedness is a condition
in which things that are near can be seen clearly, but those
that are far appear blurred or unclear. Farsightedness is a
condition in which things that are far can be seen clearly,
but those that are near are hard to see. Astigmatism
makes images appear blurred or unclear. Nearsightedness,
farsightedness, and astigmatism can be easily corrected by
wearing eyeglasses or contact lenses.
10 Science Works! 2
17. Incredible Facts
Helen Keller (27 June 1880–1 June 1968) was just a baby
when she became both blind and deaf. In spite of her disabilities,
she learned how to read and speak, and use sign language. She
wrote many books and toured 39 countries to raise awareness
and money for the visually impaired. Learn more about Helen
Keller by visiting the Braille Bug Site on http://www.afb.org/
braillebug/hKmuseum.asp (accessed on 20 June 2011).
Impaired Vision
Objectives: 1. Describe the common disorders of the eye.
2. Explain how eye disorders can affect people’s
daily activities.
3. Tell the importance of your sense of sight.
Materials: sunglasses, petroleum jelly, handkerchief, book,
sheets of paper
Procedure:
1. Rub a thin film of petroleum jelly on a pair of
sunglasses.
2. Wear the sunglasses and do the following activities:
• Read a page from a book.
• Make a paper airplane.
• Write your name on a sheet of paper.
• Walk from one end of the classroom and back to
your seat.
The Human Body 11
18. Questions:
1. How will you describe your vision while you were
wearing the sunglasses?
2. Which activity did you find the most difficult to do?
3. Which activities can you do even if your vision is
blurred?
• The eyes are your sense organs for seeing. They let you
see sizes, shapes, colors, positions, and distances of
objects.
• The eye has many parts. These include the iris, pupil,
lens, and retina.
• Nearsightedness is a condition in which things that are
near can be seen clearly, but those that are far appear
blurred or unclear.
• Farsightedness is a condition in which things that are far
can be seen clearly, but those that are near are hard to
see.
• Astigmatism is a condition that causes things to appear
blurred.
Math
Your eyes tell the shapes, colors, and sizes of objects. Observe
different objects in your school. Identify their shapes and colors.
Look for objects with the same shape. Then compare their sizes.
Do this activity with a friend to double the fun. Observe objects
together. Find the smallest square-shaped object or the biggest
circular object. Have fun observing objects with your eyes!
12 Science Works! 2
19. How well can you recognize the shapes in the picture?
Color the round objects red, the square objects brown, the
rectangular objects blue, and the triangular objects orange.
The Human Body 13
20. Lesson 3 Exploring the Sense of Hearing
Rearrange the letters to form the correct words. Use the
given clues as guide.
___________ 1. r d m r e u a – it vibrates when sound
waves reach it
___________ 2. d m i l e d e r a – it contains three tiny
bones
___________ 3. i v r b t n o a i – very fast back-and-forth
movement
___________ 4. u e r t o r a e – acts like a funnel and
catches sound waves
In this lesson, you will be able to answer the following
questions:
1. What are the parts of the ear?
2. How do your ears help you hear?
3. What are some conditions that affect one’s hearing?
4. Why is your sense of hearing important?
Your ears help you hear sound. Sound is made when
things vibrate or move back and forth very fast. Touch your
throat and speak. Do you feel movements in your throat?
14 Science Works! 2
21. The air around you is full of vibrations called sound
waves. The outer ear works like a funnel. It catches sound
waves and move them through the ear canal. At the end of
the ear canal is the eardrum. The eardrum vibrates when the
sound waves reach it. The eardrum passes these vibrations to
the three tiny bones in the middle ear. Vibrations cause tiny
receptors in the middle ear to wiggle. These vibrations create
signals that are sent to the brain.
outer ear middle ear inner ear
Sound waves
enter the outer
ear.
ear canal eardrum three tiny bones
An illness, an ear infection, a head injury, or exposure to
extremely loud sounds can damage some parts of the ear and
can cause hearing loss. Hearing loss or hearing impairment
happens when one or two ears can hear only a little sound
or no sound at all. The word deafness is also used to refer to
hearing loss.
People with hearing impairment need patience and
understanding. You may need to speak more slowly or learn
other ways to speak with them. Although their condition
is unique, you will discover that they are no different from
everyone else.
The Human Body 15
22. Incredible Facts
Did you know that sound can be measured? The loudness
of sound is measured in decibels (dB). The sound of a person’s
normal breathing is 10 dB. Heavy city traffic produces noise that
registers 85 dB.
Find out the decibel levels of different sounds to avoid
sounds that can damage your ears. Visit http://www.nidcd.nih
.gov/health/education/decibel/decibel.asp (accessed on 13
June 2010).
Using Your Ears
Objectives: 1. Listen to and identify the source of sound.
2. Give the importance of having two ears.
Materials: meterstick, chalk, notebook, pencil, blindfold
Procedure:
1. Work with a partner for this activity.
2. Pupil 1 will be the first to be blindfolded. He or she
will stand in one area of the room. Pupil 2 will mark
this area using a piece of chalk.
3. Using the meterstick, your teacher will measure
2 meters away from the spot where pupil 1 stands.
He or she will mark this spot A. Your teacher will
measure again 2 meters away from spot A and mark
this as spot B. He or she will measure again 2 meters
away from spot B and mark this as spot C.
16 Science Works! 2
23. 4. Pupil 2 will stand in any of spots A, B, or C and call
out the name of pupil 1. Pupil 1 will identify the
source of the sound by shouting A, B, or C.
5. Pupil 2 will change his or her spot eight times. Each
time pupil 2 changes his or her spot, he or she will
call out the name of pupil 1.
Pupil 1 Pupil 2
A B C
2 meters 2 meters 2 meters
6. Pupil 2 will record the number of correct answers of
pupil 1.
7. Repeat steps 3 and 4. This time, pupil 1 will cover his
or her right ear with his or her hand.
8. Switch roles with your partner and repeat the
activity.
Questions:
1. When was it easier to identify the source of sound,
when ear was covered or not covered? Why?
2. How were your results similar or different from your
partner’s results?
3. How would your life change if you could hear only
with one ear? How about if you could not hear at all?
The Human Body 17
24. • The sense organ for hearing is the ear.
• Sound is made when things vibrate or move back and
forth very fast.
• Sound waves travel through the ear and cause vibrations.
There are parts inside the ear that change these
vibrations. These vibrations create signals that are sent to
the brain.
• Continuous exposure to loud sounds is harmful and can
cause hearing loss.
Label the parts of the ear. Choose your answers from the
words in the box.
ear canal eardrum inner ear middle ear outer ear
1. 2.
3. 4. 5.
18 Science Works! 2
25. Lesson 4 Exploring the Sense of Smell
Draw a line to match each word in column A with its
meaning in column B.
A B
1. nasal cavity scent or smell
2. nostril nice or enjoyable
3. odor unlikable or horrible
4. pleasant opening of the nose through
which you breathe
5. unpleasant part of the nose that warms and
filters the air you breathe in
In this lesson, you will be able to answer the following
questions:
1. What are the parts of the nose?
2. How does your nose help you smell?
3. Why is the sense of smell important?
You learn about the world by seeing with your eyes and
hearing with your ears. What does your nose do? You can also
tell what is happening around you by your sense of smell. You
know when something is burning or when your favorite food
is cooking because you can smell their scents.
The Human Body 19
26. The air around you can carry odors or scents. Some odors
smell good or pleasant, such as the scent of perfume. Others
smell bad or unpleasant, such as the scent of rotten eggs.
You can recognize places and things by how they
smell.
The scent of an object blends or mixes
with the air. The scent enters your nostrils
when you breathe in through your nose.
The scent makes its way up to the roof
of your nasal cavity (the part of the
nose that warms and filters the air you
breathe in). The scent is turned into
signals that are sent to the brain. The
brain tells what the smell is. It might
be a pleasant smell like popcorn, or an
unpleasant smell like dirty socks.
Have you noticed that you cannot recognize the smell of
objects when you have a cold? The inside of your nose has a
slippery and sticky lining called mucus. When you have a
cold, mucus becomes thick. It covers tiny hairs in your nose.
This prevents your nose from smelling things around you.
Your sense of smell is connected to your sense of taste. This is
why food seems tasteless when you have a cold.
Using Your Nose
Precaution: Pupils with asthma or allergy should not do this
activity.
20 Science Works! 2
27. Objectives: 1. Observe and compare the ability of your nose
to detect scent.
2. Tell the importance of the sense of smell.
Materials: variety of items with distinct scent (for example,
cologne, kalamansi peeling, shampoo, bagoong),
plastic containers (one for each item), notebook,
blindfold
Procedure:
1. Work with a partner for this activity.
2. Pupil A will be the first to be blindfolded. Pupil B
will hold the items and record his or her partner’s
answers.
3. Pupil B will hold the first item under pupil A’s
nose. (Note: Do not bring the item very close to your
partner’s nose. Your partner may be allergic to some
of the items.) Pupil A will identify the item. Pupil B
will record his or her partner’s answers.
4. Repeat step 2 for the other items.
Questions:
1. Was it easy for you to identify what the items are by
using your sense of smell?
2. How were your results similar or different from your
partner’s results?
3. How would your life be if you cannot smell?
The Human Body 21
28. • The sense organ for smelling is the nose.
• The air carries scent and enters your nose when you
breathe in air. The scent travels up your nose and is
turned into signals. These signals are sent to your brain.
Your brain tells you what the smell is.
• Your nose can tell whether an odor is pleasant or
unpleasant.
Complete each sentence. Circle the correct word inside
the parentheses.
1. Your (ear tongue nose) tells the smell of things
around you.
2. Your sense of (hearing taste sight) is connected
to your sense of smell.
3. Pineapple, mango, and orange have a (pleasant
unpleasant) smell.
4. Baby powder smells (pleasant unpleasant).
5. Dirty clothes smell (unpleasant pleasant).
22 Science Works! 2
29. Lesson 5 Exploring the Sense of Taste
Arrange the letters to form the correct words. Use the
given clues as guide.
____________ 1. a i v s a l – a clear liquid, containing
water produced in the mouth
____________ 2. s t a t e u b d s – they send
messages to the brain about how something
tastes
In this lesson, you will be able to answer the following
questions:
1. What are the parts of the tongue?
2. How does your tongue help you taste?
3. Why is your sense of taste important?
As you enter your house, you notice that your mother is
baking your favorite chocolate brownies. Snack time! You can
imagine the taste of those warm brownies already. But how
do you taste food?
You taste with your tongue. Your sense of taste helps you
enjoy food. It also warns you if something is not safe to eat.
Take a close look at your tongue using a mirror. You will
see that it is not smooth. Your tongue is covered with tiny
The Human Body 23
30. “bumps” called papillae. Inside them are
taste buds. You have about ten thousand
of them! Your taste buds can sense
different kinds of taste such as sweet,
sour, salty, bitter, and umami. Umami is
the meaty or savory taste you get mostly
from cheese or meat.
When you put food in your mouth,
your teeth begin to break the food into papillae
tiny pieces. The food mixes and dissolves
with your saliva. Your saliva spreads the
flavor of food all over
your tongue. Your
taste buds pick
up the taste and
send the
message A picture of an onion-
to the shaped taste bud.
brain. Your brain tells you
the taste of the food you
are eating.
Incredible Facts
Dysgeusia is a condition in which a person cannot identify
tastes of food correctly, has a poor sense of taste, or cannot
taste anything at all. Some people lose their sense of taste as
they get older. Others have dysgeusia because of an illness.
24 Science Works! 2
31. Taste Bud Challenge
Objectives: 1. Identify different food items using the sense
of taste.
2. Use the sense of taste in comparing different
flavors of food.
Materials: 5 different food samples (for example, sugar, salt,
instant coffee, kalamansi extract, cheese), water,
plastic cups (one for each food sample), a box of
toothpicks, blindfold or big handkerchief
Procedure:
1. Work with a partner for this activity.
2. Pupil A will be the first to be blindfolded, while
pupil B will help his or her partner.
3. Pupil B will dip a toothpick in the first food sample.
He or she then places it on the tongue of pupil A.
Pupil A will tell the taste and name the food sample.
4. Pupil B will record his or her partner’s answer in
the table below. Pupil A will rinse his or her mouth
between tastes by drinking water.
5. Repeat steps 2 and 3 for the other food samples.
Food Sample Taste Name of Food Sample
1
2
3
4
6. Switch roles with your partner.
The Human Body 25
32. Questions:
1. Were the food samples easy or difficult to identify
when you were blindfolded? Why?
2. How were you able to differentiate the taste of one
food sample from the other?
• The sense organ for taste is the tongue.
• Your tongue has many taste buds embedded in it. They
send signals to the brain.
• The tongue can taste five basic tastes: sweet, sour, salty,
bitter, and umami.
Color the sweet foods red and the salty foods yellow.
Check the sour foods. Box the bitter foods. Circle the food
that tastes umami.
26 Science Works! 2
33. Lesson 6 Exploring the Sense of Touch
Complete the crossword puzzle. Read each clue below.
Choose your answer from the words in word bank.
1
Word Bank
2 cold
3
dermis
epidermis
4
heat
pain
5 pressure
skin
6
Across
2. Discomfort due to injury or sickness
4. To make or become warm or hot
5. The bottom layer of the skin
6. The top layer of the skin
Down
1. This covers the entire body
2. Force exerted on an object
3. Having little or no warmth
The Human Body 27
34. In this lesson, you will be able to answer the following
questions:
1. What are the parts of the skin?
2. How does your skin help you feel?
3. Why is your sense of touch important?
hair
The skin is the
sense organ for touch. It
covers your entire body. epidermis
Your skin is made up of
two layers. The top layer
is called the epidermis.
The bottom layer is dermis
called the dermis. The
skin has receptors that
feel pressure, heat,
cold, and pain. When
something comes in
contact with your skin, these nerve receptors send signals
to your brain. The brain tells you the effect of the touch and
tells your body how to respond to that touch. For example,
your brain tells you whether to grip or gently hold an object.
Your sense of touch or feeling also protects you. You can
sense heat and cold. The nerve receptors in your skin warn
you to pull your hand quickly from a hot stove or not to grip
sharp objects.
28 Science Works! 2
35. You can tell the
difference between rough
and smooth, soft and hard,
or wet and dry objects
because of your sense of
touch. Some parts of your
skin are more sensitive than
others. Your fingertips and
cheeks respond to heat and
cold more quickly than your Careful hand pressure is used in molding
elbows or knees do. a clay jar.
Receptor Tester
Objectives: 1. Name the parts of the body that are most
sensitive to touch.
2. Observe and find out if sensitivity to touch
varies in different parts of the body.
3. Tell the importance of your skin.
Materials: one paper clip, ruler, pencil
Procedure:
1. Work with a partner for this activity.
2. Carefully untwist the paper clip and then form it into
a U shape. (Ask the help of
your teacher in doing this.)
Use a ruler to measure the
space between the ends of the
The Human Body 29
36. U-shaped paper clip. Make sure the ends are exactly
1 centimeter (cm) apart.
3. Have your partner close
his or her eyes. Gently
touch your partner with
the bended paper clip on
the first body part given in
the table below. Ask your
partner whether he or she feels one or two points of
the paper clip.
5. Record your partner’s answer in the table. Write “1”
under the given body part if your partner feels only
one point. Write “2” if your partner feels two points.
6. Repeat steps 4 and 5 for the other parts of the body
given in the table below.
7. Switch roles with your partner.
Body Part
Back of
Fingertip Wrist Cheek Leg
the Hand
Sensitivity
Questions:
1. Which part of your body is the most sensitive? Why?
2. Which part of your body is the least sensitive? Why?
30 Science Works! 2
37. Incredible Facts
A team of scientists from Sweden
and Italy has developed Smart Hand.
This is a robotic hand that offers a
sense of touch for people who lost their
hands. This device has 4 motors that
enable the hand to move. It also has
40 receptors that let the person feel the
object that the robot touches.
Robot hand lets its user
feel and touch objects.
• The skin is your sense organ for touch or feeling.
• The skin can sense heat, cold, pain, and pressure.
• Some parts of the body, such as the cheeks and fingertips,
are more sensitive to touch than the other parts.
How does each object feel? Color two objects that the
given word can describe.
cold
The Human Body 31
38. hard
hot
rough
smooth
soft
32 Science Works! 2
39. Lesson 7 The Sense Organs Work Together
Write the missing letters to complete the words.
1. The r i n controls everything in your body.
2. Some organs can o k together to help you do some
activities.
3. The senses o l e t information from your
surroundings.
In this lesson, you will be able to answer the following
questions:
1. Do the sense organs work together?
2. Which sense organs work together in specific
activities?
Your five sense organs work together to help you do your
daily activities. For example, when you eat, your eyes look
for the food on the table. Your nose smells it. You can tell if
it is hot or cold with your hand. Your tongue tastes the food.
Your ears can sometimes hear the sound of crispy food being
chewed.
The Human Body 33
40. Your senses collect
information from your taste
touch
surroundings. Each of your
hearing
sense organs has parts that smell
send information to your sight
brain. The brain tells you
what you have seen, heard,
smelled, tasted, and touched.
Areas in the brain where each of the
five senses is located.
Senses Helping Each Other
Objectives: 1. Identify the sense organs you use in doing
certain activities.
2. Use the five sense organs to do different
activities.
Materials: sugar, evaporated milk, 2 bananas, crushed ice,
chocolate powder, 1 liter drinking water, fork,
plastic knife, spoon, plastic cups, sheet of paper
Procedure:
1. Work together in groups to make a chocolate banana
drink. Use the given ingredients under Materials and
write your own steps.
2. Copy the table on the next page on a separate sheet
of paper. Write in the table the steps you followed
and the sense organs you used for each step.
34 Science Works! 2
41. Steps Sense Organ(s) Used
Questions:
1. Were the steps you followed the same as those of the
other groups?
2. How did your senses help you prepare the chocolate
drink?
• The sense organs work together to give you information
about your surroundings.
• Each sense organ has parts that send messages to the
brain. The brain tells you what you see, hear, smell, taste,
and touch (feel).
The Human Body 35
42. Put a check ( ) mark under the sense organs that work
together in each activity.
Activity Eyes Ears Nose Tongue Skin
1.
2.
3.
4.
5.
36 Science Works! 2
43. Lesson 8 Caring for Your Sense Organs
1. __ __ r __ a __ – a yellowish wax produced in the ear
2. s __ __ __ c r __ e n – a kind of lotion that protects
the skin from sunburn
3. __ o __ s __ __ r i __ e – to add moisture to
something
In this lesson, you will be able to answer the following
questions:
1. How can you take care of your sense organs?
2. What are the things that can cause harm to your
sense organs?
3. Why should you take care of your sense organs?
Caring for Your Eyes
Do you know that your eyes can actually
clean themselves? This happens when you
blink. Blinking helps wipe the dust particles
out and wash your eyes with tears.
Do not rub your eyes when they
feel itchy. Rubbing can scratch your
The Human Body 37
44. eyes. Gently wash your eyes with clean water to lessen or
stop the itch.
If you are going out especially on a sunny
day, wear sunglasses to protect your
eyes from the harmful rays of the
sun.
Use good lighting when reading,
writing, or using the computer. Make
sure the light is not too bright.
Caring for Your Ears
When listening to music using
headphones or earphones, turn the volume
at a level that will not harm your ears.
Avoid sleeping with your headphones or
earphones on.
Use a damp cloth to clean your outer
ears. Avoid using cotton tips to clean your ear
canals. They can push the earwax deeper in your ears. Your
ear canals have a way of pushing the earwax out of your ears.
Caring for Your Nose
Keep your nose clean by wiping it gently
with tissue. Avoid nose-picking, rubbing, and
blowing your nose hard. Do not insert tiny
objects in your nose.
Blow your nose gently using tissue
or handkerchief. Throw used tissue in the
trash can and wash your hands with soap
and water after.
38 Science Works! 2
45. Caring for Your Tongue
Brush your teeth regularly. Use a tongue
scraper to clean your tongue. Cleaning your
tongue keeps your breath fresh and clean.
Avoid eating or drinking too hot or too
spicy foods as these may burn or irritate
your tongue.
Incredible Facts
The Chinese were the
first to use a toothbrush. They
used a cattle-bone for the
handle and wild boar (pig) hair
for bristles. The wild boar hair
was too stiff. It made the gums
bleed so they changed it to
horse hair. The invention of nylon (strong elastic material used in
plastic) bristles in 1937 changed the face of toothbrush.
Caring for Your Skin
Your skin covers and protects your entire body. There are
several ways you can take care of your skin.
Take a bath regularly. Give your body a light scrub to
keep your skin healthy and clean. Use water and soap to
wash your skin.
Cover any cut or wound
on your skin with a medicated
gauze and an antiseptic to keep
dirt out and to prevent infection.
Moisturize your skin so it
will not be dry, itchy, and flaky.
Choose lotions that do not have
strong scents.
The Human Body 39
46. Long exposure to the sun (between 9:00 AM to 3:30 PM)
can cause sunburn. Sunburn can be very painful. Wear a hat,
a pair of sunglasses, and a long-sleeved shirt to protect you
from the sun. Apply sunscreen if you will stay outdoors for
quite a long time.
Eat healthy foods to help sharpen your five senses. Keep
yourself safe and clean, and get plenty of rest and sleep to
avoid getting sick. Always remember that a healthy body is a
happy body.
Caring for My Senses
Objectives: 1. Identify the things that cause harm to your
sense organs.
2. Name ways of caring for your senses.
Materials: 3 pieces of bond paper, coloring materials, pencil,
old magazines
Procedure:
1. Make a booklet showing ways to care for your sense
organs.
2. Cut each bond paper in half. Fold and staple the
pieces of bond paper at the middle to make a booklet.
3. The front page of the booklet is the title page. Use
one page for each sense organ.
4. Cut out pictures showing different ways of caring
for your sense organs from magazines. You may also
draw your own pictures. Describe each picture.
40 Science Works! 2
47. • You need to care for your sense organs so that they will
work properly.
• Wear sunglasses and apply sunscreen lotion to protect
your eyes and skin from the sun whenever you go out
during the day.
• Eating healthy foods, exercising, getting enough sleep,
and maintaining cleanliness will keep your sense organs
and entire body healthy.
Circle the picture of the child who shows care for his or
her sense organs.
eyes
ears
nose
The Human Body 41
48. tongue
skin
A. Which sense organ is used to describe each object? Write
the letter of the correct answer on the blank.
a b c d e
______ 1. The kalamansi juice is sour.
______ 2. The loud sound of our school bell tells me it is
lunch time.
______ 3. A crab’s shell is rough and hard.
______ 4. My dog is big and has a brown fur.
______ 5. My sister’s perfume has a floral scent.
42 Science Works! 2
49. B. Put a check ( ) mark on the picture that gives the correct
answer.
1. Which is not a proper way of caring for the eyes?
2. Which practices are harmful to your ears?
The Human Body 43
50. 3. Which of the following should you use to clean your
nose?
4. Which of the following shows proper care for the
tongue?
44 Science Works! 2
51. 5. Which of the following shows proper care for the
skin?
C. Color the sense organs that work together in each activity.
1.
nose
ears
tongue
skin
eyes
2.
ears
eyes
skin
tongue
nose
The Human Body 45
