Sample E Book

CONTENTS UNIT 1: Investigating Living Things 1: Living Things Have Basic Needs 1.1 The Basic Needs of Humans 03 1.2 The Basic Needs of Animals 14 1.3 The Basic Needs of Plants 19 2: Living Things Undergo Life Processes 2.1 Life process in Humans 29 2.2 Bad Habits that Disturb Life Processes 32 2.3 Life process in Animals 34 2.4 Life process in Plants 39 3: Animals and plants Protect Themselves 3.1 Special Characteristics of Animals 49 3.2 Special Behaviour of Animals 53 3.3 Animals Protecting Themselves from Extreme Weather 59 3.4 Plants Protect Themselves from Danger 62 3.5 Plants Protect Themselves from Extreme Weather 66 1

2 Living Things Undergo Life Processes What you will learn Keywords • Process of breathing, excretion and • Excretion defecation in humans • Defecation • Stimulus • Importance of excretion and defecation in • Response animals • Fungi • Inhalation • Impact of unhealthy lifestyle on life • Exhalation processes • Spiracles • Trachea • Breathing structures of different animals • Gills • Classification of animals based on the type • Suckers of reproduction • Response to stimuli in humans and plants • Parts of plants that respond to stimuli • Different types of plant reproduction Let us begin! Write Yes or No in the space given below the column A and B by referring the pictures given in the respective columns. Column A Column B Actions Kitten Table Do they eat? Do they move? Do they breathe? 28

A balanced diet is a meal that contains food from all the groups in the right proportion. This group of food items gives you energy but should be consumed in lesser quantities. This group of food items help to build strong bones and muscles. This group of food items protect you from diseases. This group of food items help you to grow and also gives energy to work. 1.4 Balanced Diet Water Water is an important component in our day-to-day life. It is essential for all the living beings. Drinking enough water helps in the digestion of food. 1.5 A boy drinking water 7

1.2 The Basic Needs of Animals It is important to know that just like human beings, animals too require water, food, air and shelter, and can survive only in the environments where these basic needs are available. Different animals have different types of environment that support their lives. Observe the animals in the figure 1.14. You see the rabbit eating carrots, fish breathing in water, penguins living in ice lands and a bird drinking water with its beak. 1.14 Basic Needs of Animals Animals cannot survive without food, air, water and shelter. Animals need Food We need food as it gives us energy to do work and other activities. Similarly, animals too need food. Animals need energy to move from place to place in search of food and water, to run and catch their prey, as well as to escape from their predators. 1.15 Animals move from place to place 14

3.1 Special Characteristics of Animals Some animals have special characteristics that enable them to protect themselves from danger. Some of them are: 1. The presence of hard scales Animals such as crocodile, pangolin, snake and fish have hard scales on their skin for protection. 3.1 Crocodile 3.2 Pangolin 3.3 Snake 3.4 Fish 2. The presence of pointed spines Animals such as porcupine, hedgehog and some fish (eg: porcupine fish) have pointed spines on their body that is used for protection. 3.5 Porcupine 3.6 Hedgehog 3.7 Porcupine fish 49

Example 1: Write the place value of every digit in the number 7 343 216. Solution: Write each digit in its place in the place value chart. Place Millions Hundred Ten Thousands Hundreds Tens Ones value thousands thousands Digit 7 3 4 3 2 16 6x1=6 Place 1 x 10 = 10 value 2 x 100 = 200 of each 3 x 1 000 = 3 000 digit 4 x 10 000 = 40 000 3 x 100 000 = 300 000 7 x 1 000 000 = 7 000 000 Example 2: Write the place value of the digits 9 and 2 in the number 1 902 630. Solution: Place the number in the place value chart. Place Millions Hundred Ten Thousands Hundreds Tens Ones value 1 thousands thousands 2 6 30 Digit 9 0 Place value of 9 9 is in the hundred thousands place So 9 x 100 000 = 900 000 Place value of 2 2 is in the thousands place So 2 x 1 000 = 2 000 The names of the places can be written in the short form for convenience. Place Millions Hundred Ten Thousands Hundreds Tens Ones value M thousands thousands Th H TO Short form H th T th 5

Subtraction of mixed numbers by converting them into improper fractions Example 1: 9 5 - 3 1 - 1 1 6 3 6 Solution: Convert the mixed fractions into improper fractions. 9 5 59 -3 31 10 - 1 61 7 6 6 3 6 Make the denominators of the given fractions equal. 10 x 2 59 - 130 20 - 7 6 6 6 3x2 = 59 - 20 - 7 = 32 = 5 2 6 6 6 6 6 5 2 in its simplest form is 5 1 6 3 Therefore, 9 5 -3 1 - 1 1 =5 1 6 3 6 3 Steps to be followed while solving word problems • Understanding the problem • Devising a plan • Implementing the plan ESxheamtrapvleels1:5S12arakmtrabvyelbsu1s1, 1480 km daily. 1 km by 5 auto and the rest by walk. Find the distance travelled by Sara by walk alone. Solution: Understanding the problem: 8 10 Total distance travelled by Sara everyday = 11 km Distance travelled by bus = 5 1 km 2 33

Step 2: Hundreds Tens Ones Tenths Hundredths Thousandths 4 9 0 . 10 0 7 1 0 - 30. 3 0 3 4 60. 7 0 4 Therefore, 794.037 – 303.03 – 30.303 = 460.704 Example 3: Adam and Jack were running a relay race. The distance to be run was 33.03 km in total. If Adam ran 16.93 km, how many km did Jack run? Solution: Understanding the problem: The total distance of the relay race = 33.03 km Distance covered by Adam = 16.93 km Distance covered by Jack = ? Devising a plan : Subtraction Implementing the plan: 33.03 km - 16.93 km Tens Ones Tenths Hundredths 2 123 . 100 3 3 1 6. 9 3 1 6. 1 0 Therefore, Jack ran 16.1 km. 71

Decimals and Fractions Whole numbers can be expressed as decimals of a million and vice versa. Divide by 1 000 000 or move the Multiply by 1 000 000 or move the decimal six places to the left to decimal point six places to the right express a whole number as a to express the decimal of a million decimal of a million. as a whole number. 5 230 000 = 5 2 3 0 0 0 0 = 5.23 0.6 million = . 6 0 0 0 0 0 = million 600 000 Example 1: 400 000 = 0.4 million Example 1: 0.9 million = 900 000 Example 2: 7 350 000 = 7.35 million Example 2: 2.173 million = 2 173 000 Whole numbers can be expressed as fractions of a million and vice versa. 5 100 000 = 5 000 000 + 100 000 100 000 = 5 million + 1 000 000 5 100 000 = 5 110 milli o n = 5 mil l ion + 1 million 10 = 5 110 million 3 15 milli on = 3 200 000 51 millio n = 1 x 1 000 000 5 = 200 000 Example 1: 2 500 000 = 2 1 million Fractions of a million 2 Example 2: 4 250 000 = 4 1 million 1 of a million = 250 000 4 4 Example 3: 7 3 million = 7 750 000 1 of a million = 500 000 4 2 Example 4: 6 1 million = 6 500 000 3 of a million = 750 000 2 4 6

Example 2: A photo album worth RM 150 was sold at RM 90. Find the percentage of discount. Understanding the problem: RM 150 Marked price of the photo album = RM 150 RM 90 Selling price of the photo album = RM 90 To find the percentage of discount. Devising a plan: Discount amount = Marked price – Selling price P ercen tage D iscount = DisMcaoruknetdapmriocuent x 100% Implementing the plan: Discount amount = RM 150 – RM 90 = RM 60 Percentage of Discount 4 60 x 100 = 40% 150 = 1 Therefore, the photo album worth RM 150 was sold at a discount of 40%. Percentage of Profit or Loss If the goods are sold for more than the cost price or original price, the seller gets a profit. Similarly, if the goods are sold for less than the cost price or original price, the seller gets a loss. Example 1: A wall shelf worth RM 90 was sold at RM 72. Find the percentage of loss. Understanding the problem: RM 90 Original price= RM 90 RM 72 Selling price = RM 72 To find the percentage loss. Devising a plan: Percentage Loss = Loss x 100% Original price Implementing the plan: Loss = RM 90 - RM 72 = RM 18 Percentage of Loss 2 18 x 100 = 20% 90 = 1 Therefore, the wall shelf was sold at a loss of 20%. 68

Example 3: Calculate (RM 450 x 12) + RM 16 590.00 Solution: (RM 450 x 12) + RM 16 590.00 RM 5 400 + RM 16 590.00 = RM 21 990.00 Therefore, (RM 450 x 12) + RM 16 590.00 = RM 21 990.00 Example 4: Calculate RM 560 000 – (RM 45 000 ÷ 25) Solution: When brackets are involved, first do the operation in the brackets. 560 000 – ( RM 45 000 ÷ 25) RM 1 8 0 0 RM 560 000 – RM 1 800 25 RM 45 000. 00 5 9 10 25 200 RM 560 000.00 200 –RM 1 800.00 0 RM 558 200.00 Therefore, RM 560 000 – (RM 45 000 ÷ 25) = RM 558 200.00 Example 5: Calculate (RM 540 x 72) + (RM 72 585 ÷ 9) Solution: When brackets are involved, first do the operation in the brackets. (RM 540 x 72) + (RM 72 585 ÷ 9) 2 RM 8 0 6 5 RM 38 880 + 8 065 = RM 5 4 0 9 RM 7 2 5 8 5. 0 0 11 x 72 72 RM 38 880 1080 58 + RM 8 065 + 3780 54 RM 46 945 RM 3 8 8 8 0 45 45 0 Therefore, (RM 540 x 72) + (RM 72 585 ÷ 9) = RM 46 945 80

• Estimate all the given numbers in a problem to the same place value. Estimate the sum of 25 680, 6 875, 435 Nearest 1 000 Nearest 100 Numbers 25 680 26 000 25 000 25 700 25 600 6 875 7 000 6 000 6 900 6 800 435 400 400 500 0 • Place the product of the numbers in the correct starting point. Solve: 857 x 42 8 5 7 857 X 42 X 4 2 1714 1 7 1 4 34280 3 4 2 8 35994 5 1 4 2 • Digit 0 should be placed in the quotient if the numbers cannot be divided by the dividend. Solve: 75 036 ÷ 15 5 0 2 5002 15 7 5 0 3 6 15 7 5 0 3 6 - 7 5 - 75 0 0 3 6 0 0 3 6 - 3 0 - 30 6 6 30