Smart Science 2Textbook

Smart Science Grade 2TexTbook

Philippine Copyright 2009 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 by DIWA LEARNING SYSTEMS INC 4/F SEDCCO 1 Bldg. 120 Thailand corner Legazpi Streets Legaspi Village, 1229 Makati City, Philippines Tel. No.: (632) 893-8501 * Fax: (632) 817-8700

ISBN 978-971-46-0087-4

RevieweR

Marina Balce was a former assistant dean and associate professor at the College of Education, La Salle College–Antipolo. She taught biological sciences for Psychology students and thesis writing for graduating Education students in the same college. She was also a Trainee of the Japan International Cooperation Agency (JICA) at the Aichi University in Nagoya, Japan, where she attended a special training on Practical Work in Elementary School Science. Dr. Balce finished her bachelor’s degree in Secondary Education major in Biology at the University of the East–Manila. She has a master’s degree in Biology Education from the De La Salle University–Manila and a doctorate in Science Education major in Biology from the University of the Philippines–Diliman.

To the Learner Doyouaskyourselfquestionsabouttheworldyoulivein?Doyouwonderaboutwhatliesbeyondtheblueskiesorwhatrestsbelowtheseas?Doyouaskquestionsaboutthebloomingtreesandcolorfulflowersyousee,theheatandcoldyoufeel,orthevariousscentsyousmell?Doyouwonderaboutthesun,themoon,andthestars?Youryoung,activemindhassomanyquestionsbecauseyouarecuriousaboutsomanythings.

Thisbookwillhelpyoudiscovertheanswerstothequestionsyouhaveaboutyourself,theworld,andeverythingbeyondit.Thisbookwillbeyourconstantcompanionasyouunlockthemanymysteriesoflifethroughvariouslearningexperiences.Moreover,thisbookwillteachyouhowtoapplythewondersofsciencetoyourday-to-dayactivities.

Letthisbookhelpyoufindtheanswerstothequestionsyouhaveaboutyourself,yourworld,andyouruniverse.Letthistakeyouastepclosertounderstandinglifeandindiscoveringthewondersofscience!

Unit 1 Your Body

Chapter 1 Your SensesLesson1 TheThingsaroundYou.............................................................2Lesson2 WhatDoYouSee?....................................................................8Lesson3 WhatDoYouHear?................................................................13Lesson4 WhatDoYouSmell?...............................................................18Lesson5 HowDoesItTaste?..................................................................22Lesson6 WhatDoYouFeel?.................................................................27Lesson7 YourSenseOrgansWorkTogether..........................................31ThinkBack ...............................................................................................35MeasureUp!...............................................................................................36

Chapter 2 Your Body’s Needs

Lesson1 FoodThatMakesYouGrow....................................................37Lesson2 FoodThatMakesYouGo........................................................41Lesson3 FoodThatMakesYouGlow....................................................44Lesson4 HealthyEatingHabits..............................................................48Lesson5 YouAreGrowing....................................................................52Lesson6 ThingsThatYouCanDoNow.................................................55ThinkBack ...............................................................................................59MeasureUp!...............................................................................................59

Unit 2 Wonders of Nature

Chapter 3 The Animal KingdomLesson1 HowAnimalsMove.................................................................62Lesson2 HowAnimalsEat.....................................................................67Lesson3 AnimalsNeedAir....................................................................71Lesson4 AnimalDefenses.....................................................................74

Lesson5 AnimalsoftheSameKindHaveSimilaritiesandDifferences...79Lesson6 AnimalsofDifferentKindsHaveSimilarities............................83Lesson7 YoungAnimalsandTheirParents............................................87Lesson8 TakingCareofAnimals...........................................................93ThinkBack ...............................................................................................97MeasureUp!...............................................................................................97

Chapter 4 The Plant KingdomLesson1 PlantsGrow.............................................................................99Lesson2 YoungandMaturePlants.......................................................103Lesson3 PlantsoftheSameKindHaveSimilaritiesandDifferences.....106Lesson4 SomePlantsBearFlowersandFruits......................................110Lesson5 BasicNeedsofPlants............................................................116Lesson6 UsesofPlants........................................................................123ThinkBack .............................................................................................128MeasureUp!.............................................................................................128

Unit 3 Matter and Energy

Chapter 5 Matter and YouLesson1 MatteraroundYou................................................................132Lesson2 PhasesofMatter....................................................................136Lesson3 ShapeandVolumeofSolids..................................................139Lesson4 MassofSolids........................................................................143Lesson5 LiquidsTakeupSpace...........................................................147Lesson6 MassofLiquids......................................................................151Lesson7 GasTakesupSpace...............................................................154Lesson8 GasHasMass........................................................................157ThinkBack .............................................................................................160MeasureUp!.............................................................................................161

Chapter 6 Energy around YouLesson1 LightandHeat.......................................................................164Lesson2 LightTravels..........................................................................172Lesson3 LuminousandNonluminousObjects....................................175Lesson4 SoundIsEverywhere.............................................................178Lesson5 MagnetsCanAttractOtherObjects.......................................182ThinkBack .............................................................................................185MeasureUp!.............................................................................................185

Unit 4 Earth and Beyond

Chapter 7 Earth, Weather, and YouLesson1 EarthandItsLandforms.........................................................188Lesson2 EarthandItsBodiesofWater.................................................193Lesson3 EarthGivesUsefulThings......................................................198Lesson4 NaturalEventsThatChangeEarth..........................................204Lesson5 HumanActivitiesThatChangeEarth......................................209Lesson6 TakingCareofMotherEarth..................................................213Lesson7 DifferentKindsofWeather....................................................220Lesson8 WeatherReport.....................................................................225Lesson9 ObservingSafetyMeasuresduringBadWeather....................229ThinkBack .............................................................................................233MeasureUp!.............................................................................................233

Chapter 8 The Solar SystemLesson1 Earth’sNearestNeighbor.......................................................235Lesson2 TheBrightSun.......................................................................239Lesson3 TheSunandItsFamily..........................................................243ThinkBack .............................................................................................246MeasureUp!.............................................................................................247

Bibliography...................................................................................................249

Unit 1 Your Body

Your body has parts that help you do things. You see beautiful places through your eyes. You hear sounds because of your ears. You smell the scent of flowers in your garden because of your nose. You can taste food because of your tongue. You can feel your pillow because it touches your skin.

You should take good care of your body. One way to keep your body strong and healthy is to eat the right kind and amount of food.

� Smart Science 2

Chapter 1

Lesson 1The Things around You

Your Senses

Your sense organs help you collect information about the things in your surroundings. They send all these information to your brain. Without your sense organs, you will not be able to see, hear, smell, taste, and feel anything.

Find Out

1. What are your sense organs?2. Where do sense organs send all

the information they get from the surroundings?

One sunny Saturday afternoon, Gino and Lea went to the park. As they were walking, they felt the rough pebbles underneath their shoes.

“Oh, my! It’s so hot today!” Gino cried out.

“Tweet! Tweet! Tweet!” Lea and Gino heard the birds singing. They ran to the trees where the birds were. But the birds quickly flew away.

�Your Body

You can tell how objects look by their colors, sizes, or shapes using your eyes.

You can describe and know objects by their smell using your nose.

As they continued to walk, Gino and Lea suddenly felt thirsty and hungry. They decided to go to Nina’s house.

When they were nearing Nina’s house, they smelled something. “Hmmm! I smell sopas,” Gino said. “I smell banana cue,” Lea added.

“Yum . . . yum . . . yum . . . This sopas is delicious!” Gino said as he sipped it. “This banana cue also tastes great!” Lea said.

Do you know what makes you see, hear, smell, taste, and feel? Your body has sense organs that collect information about what you see, hear, smell, taste, and feel. These sense organs send the information to your brain. Your brain then tells you what you have seen, smelled, tasted, heard, and felt.

� Smart Science 2

You can also describe and know objects by the sounds they make using your ears.

You can describe the objects by their taste using your tongue. These tastes can be sweet, bitter, sour, salty, or umami.

You can describe and know objects by touching them. You can feel smooth and rough objects using your skin.

�Your Body

Sense It!

1. There are five small boxes on the table. The boxes labeled A, B, C, D, and E contain one object each.

2. Pick out the object from Box A. What is the object? Describe it using your eyes.

3. Shake Box B. What do you hear? Guess what the object is.

4. Smell Box C. What is the object inside it?

Note: If you are asthmatic, skip this step.

5. Get a partner and let him or her blindfold you. Your partner will pick an object from Box D and will let you taste it. What does it taste like? What is the object?

Explore

� Smart Science 2

7. Which sense organ did you use to identify the object in each box?

Box Sense OrganA

B

C

D

E

6. Touch the object inside Box E. Is the object smooth or rough? What is the object?

Your sense organs gather information from your surroundings which they send to your brain. Without them, you cannot see, hear, smell, taste, and feel anything.

Keep in Mind

�Your Body

List five things that can be found in the classroom. Describe each using the table below. Name the sense organs you used to describe each object.

Object ColorSize

(big or small)

Sound Produced(loud or

soft)

Smell (pleasant or unpleasant)

Taste (sweet,

sour, bitter, salty, or umami)

Shape

Texture (rough

or smooth)

1.

2.

3.

4.

5.

Sense organs used:Object 1 _______________________________________________

Object 2 _______________________________________________

Object 3 _______________________________________________

Object 4 _______________________________________________

Object 5 _______________________________________________

Challenge Yourself