202110323-MAGNOLIA-STUDENT-TEXTBOOK-EVS_I(SCIENCE)-G04-PART1

EVS – I (SCIENCE) TEXTBOOK – PART 1 4 Name: ___________________________________ Section: ________________ Roll No.: _________ School: __________________________________

Preface IMAX partners with schools, supporting them with learning materials and processes that are all crafted to work together as an interconnected system to drive learning. IMAX Program presents the latest version of the Magnolia series – updated and revised after considering the perceptive feedback and comments shared by our experienced reviewers and users. The Magnolia series endeavours to be faithful to the spirit of the prescribed board curriculum. Furthermore, to facilitate comprehensive coverage, improved understanding of diverse themes and ease of implementation, the EVS curriculum has been split into EVS – I (Science) and EVS – II (Social Studies). Our books are split into two parts to manage the bag weight. They also strive to ensure inclusiveness in terms of gender and diversity in representation, catering to the heterogeneous Indian classroom. The Magnolia EVS – I (Science) textbooks and workbooks offer the following features:  Interactive content that engages students through a range of open- ended questions that build curiosity and initiate exploration  Opportunities for experimentation, analysis and synthesis of ideas and concepts  Exposure to locally relevant environmental problem solving  Effective use of visual elements to enable learning of structures, processes and phenomena  A focus on subject-specific vocabulary building  Integrated learning of values and life skills  Promotion of participatory and contextualised learning through the engagement of all relevant stakeholders in the learning process Overall, the IMAX Magnolia EVS – I (Science) textbooks, workbooks and teacher companion books aim to inculcate healthy habits, skills and values that promote environmentally sensitive and culturally responsive democratic citizenship among students. – The Authors

Textbook Features Let Us Learn About Think Contains the list of learning objectives to Introduces the concept/subtopic and be achieved in the lesson arouses curiosity among students Understanding Remembering Explains the aspects in detail that form Introduces new concepts to build on the basis of the concept the prerequisite knowledge/skills required Includes elements to ensure that students to understand and apply the objective are engaged throughout of the topic Application Amazing Facts Connects the concept to real-life Fascinating facts and trivia related to situations by enabling students to apply the concept what has been learnt through the practice questions Higher Order Thinking Skills (H.O.T.S.) Encourages students to extend the concept learnt to advanced application scenarios Inside the Lab Provides for hands-on experience with creating, designing and implementing something innovative and useful

Contents 4Class 1 Growing up with Family�����������������������������������������������������������������������������������������������1 2 Digestive System����������������������������������������������������������������������������������������������������������5 3 Excretory System����������������������������������������������������������������������������������������������������������8 4 Diseases����������������������������������������������������������������������������������������������������������������������12 5 Keeping Our Neighbourhood Clean�����������������������������������������������������������������������17 Inside the Lab – A�������������������������������������������������������������������������������������������������������������21 Activity A1: Digestive System Activity A2: Disease Prevention Charades 6 Water Storage and Quality����������������������������������������������������������������������������������������23 7 Importance of Soil������������������������������������������������������������������������������������������������������29 8 Roots and Flowers������������������������������������������������������������������������������������������������������33

Lesson Growing up with Family 1 Let Us Learn About R y oung ones of animals and human babies. u taking care of babies. a adopting babies and animals into the family. h the roles of family members in caring for a baby. Think A stray dog in Reena’s neighbourhood gave birth to seven puppies. Reena and all her friends liked the cute puppies. Each of them decided to take a puppy home and take care of it. Have you or your friends ever done this? Remembering Do you like to play with kittens, chicks or puppies? They are the young ones of different animals. Where do you think they come from? Some animals lay eggs, and the young ones hatch out of them. The hen, fish, frog, snake and lizard are a few animals that lay eggs. Have you ever seen a bird coming out of its egg? 1

a hen and its eggs a chick coming out of an egg a snake and its eggs Some animals give birth to their babies. It means that the babies come out from their mothers’ bodies. Animals like the cat, cow, dog, horse, elephant and lion give birth to babies. Humans also give birth to babies. a dog with puppies a lion with a cub a mother with a baby A human baby grows inside its mother’s body for nine months before being born. Puppies and kittens grow inside their mothers’ bodies for about two months. Calves grow inside mother cows for about nine months. Understanding Young ones of animals mostly depend on their mother for food. Animals that lay eggs collect food and feed their babies. Have you ever seen how a baby bird is fed by its mother? Animals that give birth to young ones feed the babies on their milk. You might have seen calves, kittens or puppies drinking milk from their mothers’ body. a cow feeding its calf a bird feeding its young ones a cat feeding its kittens 2

Like other baby animals, a human baby also depends on its parents taking care mother for food and protection. When a baby is born, the of a baby mother and father take care of their baby with the help of other family members. Babies need a lot of time and care an older brother spending time from their parents. Your parents have taken care of you since with a younger sibling you were a baby. Do you have a younger sibling? Do you like to spend some time with him or her? How do you take care of your sibling? Sometimes, if a mother spends more time with a baby to take care of it, an older child may feel left out. Do you know your mother and father were also born as small babies? Their parents too took care of them. Maybe, they went to school when they were small. They also had homework to do. They may have played with their friends and learnt new things. Their parents even scolded them for being naughty and doing something wrong! They may have fought with their siblings and cried. Ask your parents what they did when they were kids. babies grow up to become adults Application Sometimes, the young ones of animals lose their mother. Have you seen small puppies left alone without a mother to look after them? Sometimes some other animals may look after those young ones. Also, some people may bring them home and keep them as their pets. animals taking care of the young ones of other animals 3 Growing up with Family

Similarly, some children also may lose their parents. The children who have lost both their parents are called orphans. Some parents may take up the responsibility of such babies or children. Some families bring home a child of other parents as their own child. They make them part of their own family. This is called adoption. The parents who adopt them are called adoptive parents. They love and take care of their new child as their own. After adoption, the adopted child lives with his or her new parents in his or her new home. Suppose you have adopted a puppy. What will you do to take care of it? How can you make sure that the puppy is well taken care of? Do you have any friends or relatives who have adopted young ones of any animals? Amazing Facts Did you know that the young ones of the cuckoo are taken care of by other birds? Cuckoos always lay their eggs in the nests of other birds. So, their young ones are fed and brought up by those birds. a bird feeding a cuckoo chick Higher Order Thinking Skills (H.O.T.S.) You have learnt about adoptive parents. Sometimes, people take up the responsibility of a child without adopting them. They are called foster parents. A foster parent may take up the responsibility of many children who were not born to them. Growing up with the care of parents and family is important for children. A child needs the care of all family members. Who takes care of you at home? Which family member spends more time with you? Generally, mothers spend more time to look after their babies. What are the things a father can do for a baby? Find out. 4

Lesson Digestive System 2 Let Us Learn About R digestion and the digestive system. u the process of digestion. a the importance of the digestive system. h hunger and famine. Think Your mother tells you to chew your food before swallowing it. Do you know why? chewing food Remembering We do a lot of work throughout the day. We need energy to work. activities we do From where do we get this energy? This energy comes from the food we eat. Food contains proteins, fats, carbohydrates, vitamins and minerals. Our body cannot absorb them directly. So, they are broken down into smaller parts. The process of breaking down food into smaller parts that can be absorbed into the bloodstream is called digestion. The organ system in our body that helps in breaking down the food is called the digestive system. When the food is broken down, we get energy to do many things. 5

Look at the picture of the digestive system. The different parts of the digestive system are: Mouth: We put food in our mouth. Food pipe: It is a long tube Digestion starts here with the help that connects the mouth of the teeth and tongue. with the stomach. Liver: It is the largest and Stomach: It is a stretchy bag- heaviest organ in the like organ. When the stomach body. It is reddish brown. is empty, it is about the size of a tennis ball. After a big meal, Small intestine: It is a long, it expands almost the narrow tube. It is twenty- size of a football. two feet long. Large intestine: The large Anus: It is the opening intestine is also like a tube. It is at the end of the five feet long. It is called the digestive system. large intestine because it is wider than the small intestine. the human digestive system What happens to the food after we eat it? Let us find out. Understanding Digestion starts in the mouth. We chew the food with our teeth. We have different types of teeth to chew the food and break it into pieces. The sharp teeth in the front help us to bite and cut the food into smaller pieces. The back teeth are flat and help to grind the food into a paste. Saliva mixes with the food. Saliva is produced inside our mouth. It mixes digestion starts in mouth with the food and makes the food soft and wet. Teeth can now easily break down this wet food into smaller pieces. The tongue helps in mixing the food with the saliva. It also pushes the chewed food towards the food pipe. The food pipe moves the food from the back of our throat to our stomach. Stomach walls make squeezing and relaxing movements. These movements help to mix the food with the stomach juices. The stomach juices help to break down the food. From the stomach, the food goes into the small intestine. The liver produces bile juice. It helps in the digestion of food. stomach movement In the small intestine, the bile juice mixes with the food and breaks it down further. The walls of the small intestine absorb all the useful parts of the food. 6

Digestion of food gets completed in the small intestine. The remaining undigested material is pushed to the large intestine. When the food passes through the large intestine, water and some minerals get absorbed by the walls of the large intestine. Then it pushes the remaining waste matter into the anus. Anus pushes the undigested food waste out of the body. Application We get energy from the food we eat. So it is important to: • eat healthy food • take care of different organs of the digestive system What will happen if we do not eat food? If we do not eat food, the body will not get the nutrients and energy it needs to work. So, we will feel tired quickly. If we do not eat for very long periods of time, our body will become thin and weak. Due to the lack of nutrients, we may also become sick. What will happen, if our digestive system does not work? The food we eat will not get broken down. We will have indigestion. Indigestion may cause stomach pain, vomiting and so on. It is essential to take care of our mouth. It helps in digestion and tasting food. So, for a healthy digestive system, we must keep our mouth, tongue and teeth clean. Amazing Facts Do you know that the mouth produces about 1.7 litres of saliva every day? This amount is almost the same as that of a big bottle of Coca-Cola. Salivary glands in our mouth produce saliva. Higher Order Thinking Skills (H.O.T.S.) Why do we feel hungry after every few hours? Our body needs constant energy and nutrient supply to work. Once the food we eat gets digested and the nutrients are absorbed, we feel hungry. Hunger is the weakness caused by lack of food accompanied by a feeling to eat. It makes us tired. Have you ever felt hungry and did not get anything to eat for some time? Many people in the world do not get enough food to eat. They remain hungry. Imagine how difficult their life must be! Sometimes, in some places, there will be a widespread shortage of food. This shortage of food is called famine. During a famine, many people may die due to lack of food. Digestive System 7

Lesson Excretory System 3 Let Us Learn About R excretion and the excretory system. U the process of excretion. A the importance of the excretory system. H kidney stones. Think We drink a lot of water throughout the day. There is some water in the food we eat too. What happens to all this water we take in? Remembering We have learnt earlier that our body gets the energy to work from the food we eat and the liquids we drink. The blood in our body absorbs the useful parts from the food and liquids that we take in. The unused food and water become waste. Leftovers from food in the body form solid waste. Leftovers from water and other liquids we drink form liquid waste. Various processes taking place inside our body also produce waste. 8

Removal of waste from the body is called excretion. We get rid of the waste from the air that we have taken in by breathing it out. We get rid of solid waste by pooping and liquid waste by peeing and sweating. We have learnt that the digestive system gets rid of most of the solid wastes from our body. The organ system which removes the liquid waste from our body is called the excretory system. Look at the diagram of the excretory system. It includes the following organs: 1) A pair of kidneys: They are two bean-shaped kidney structures located near our stomach, one on ureter each side of our backbone. They are about the size of our fist. 2) A pair of ureters: They are pipe-like structures. One ureter is attached to each kidney. 3) Urinary bladder: It is a bag-like structure that urinary bladder expands as it fills with urine. It is balloon-shaped when filled. 4) Urethra: It is a pipe-like structure at the end of urethra the bladder. It opens outside the body. the human excretory system Understanding Now let us learn how different excretory organs help in excretion. As the blood travels throughout the body, it collects more and more waste. The kidneys work like a filter. When the blood enters the kidneys, they filter the blood which passes through them. It takes about 45 minutes for the kidney to purify (clean) all the blood in our body. Kidneys work throughout the day. Kidneys send all the waste to the bladder through the ureters in the form of urine (commonly known as pee). The urinary bladder stores this urine. When the bladder is almost half full, we feel like peeing. During peeing (urinating), the urine from the bladder is thrown out through the urethra. In this way, liquid waste is removed from the blood and thrown out of our body as urine. Excretory System 9

Organs like the skin and lungs are also involved in throwing out wastes. Let us see how this happens. 1) Excretion through the skin: Skin is the largest excretory organ in our sweating body. The liquid waste from our body is thrown out in the form of sweat. It is made up of extra water and salts from our body. Sweat cools our body. 2) Excretion through lungs: We breathe in and out with the help of our lungs. During breathing, the lungs absorb the oxygen from the air we breathe. At the same time, carbon dioxide is thrown out of the body from the lungs as a waste. breathing Application The excretory system removes waste from the body. If it does not work properly, the liquid wastes collect inside the body. This may lead to swelling of the body, especially on the legs, hands and face. If our kidneys don’t work properly, the colour and smell of the urine may change. We may feel tired, or we may start vomiting. How do we take care of the excretory organs? Have you heard of any fruit or vegetable that helps to keep our kidneys healthy? Find out more about such food items which can improve the working of our excretory system. Our skin and lungs also perform excretion. We should take care of them too. We should bathe regularly to take care of our skin. We should keep it clean using soap and water. We must do breathing exercises to keep the lungs healthy. We must protect our lungs from dust and smoke by wearing a mask when we go outside. Amazing Facts Most humans urinate about 3000 times in a year. On an average, we take 21 seconds to urinate. That is about 18 hours a year! Higher Order Thinking Skills (H.O.T.S.) Have you heard about kidney stones? They are the solid pieces of salt or minerals formed inside the kidneys. They vary in size. When they are small in size, like a grain of salt or sugar, 10

they do not cause any problem. They come out of the body along with the urine. But when they are of the size of a pea, they block the ureter. This causes pain. How do kidney stones develop in kidneys? Kidney stones are formed due to excess salts and minerals in the urine. This may happen if we do not drink enough water. So, we should drink plenty of water to avoid the formation of kidney stones. kidney stones Excretory System 11

Lesson Diseases 4 Let Us Learn About R diseases and prevention. u types of diseases. a the prevention of various types of diseases. h epidemics. Think Vinay’s father woke up one morning with his nose red. His eyes were swollen. The doctor gave him medicines. He became healthy in a week. What do you think had happened to Vinay’s father? Remembering A disease is an unhealthy thing happening to the body or mind. There are many diseases that affect humans. For example, common cold, chickenpox, malaria, asthma, diabetes and many more. When we are unwell, our body shows some external signs that something is wrong. The signs could be a headache, stomach pain, runny nose, fever, cough, shivering and vomiting. These signs are called symptoms. They help the doctor identify why we have ill health. This method of identifying a disease from its signs and symptoms is called a diagnosis. The best way to protect our body from diseases is to keep disease-causing germs away from our body. This is called the prevention of disease. 12

Understanding Some diseases can spread from one person to another. Some diseases do not spread from one person to another. Let us learn about them. DISEASES that spread DISEASES that do not spread Some diseases spread from one person Some diseases are not caused by germs. to another. These are caused by disease- These diseases do not spread from one causing germs. Germs are very tiny. They live person to another. Let us discuss some of the all around us; in the air, water, food and so causes of such diseases: on. They are not visible to the human eye. Most of the germs are not harmful, but some 1 The body needs nutrients like vitamins, cause diseases. Germs attack our body minerals and proteins. If the body does when it is weak. not get all these through the food we Germs spread in different ways. They can eat, we become ill. spread through touch, food, water and air. Based on the way they spread, diseases are Vitamins are of different types such as of different types: A, B, C, D, E and K. 1 Diseases that spread through the air Important minerals needed for our body are called airborne diseases. Germs are calcium, iron, phosphorus and so on. from unhealthy people spread through the air when they cough or sneeze. Disease caused Due to lack of When other people breathe in the same air, these germs may enter their night blindness vitamin A body through the mouth or nose. They can cause diseases such as common scurvy vitamin C cold, chickenpox and measles. beriberi, pellagra vitamin B 2 D iseases that spread through water are called waterborne diseases. Example: anaemia iron typhoid, dysentery and cholera goitre iodine 3 S ome diseases spread through touch. Germs from diseased people may 2 Sometimes, our internal organ systems stick to things they touch and to do not work properly due to different clothes they wear. Touching those reasons. This can cause diseases. things, then touching your eyes, nose, Example: liver disease and heart failure mouth, or a cut on the body may allow germs to enter the body. 3 Harmful substances in food, water and air can also cause diseases. 4 S ome diseases are spread by insects Example: allergies such as mosquitoes and houseflies. Example: malaria, dengue and 4 E xtreme hot or cold weather can also chikungunya cause some diseases or allergies. Example: heatstroke and frostbites 5 Some diseases are passed on to children from their parents at the time of birth. Example: haemophilia Diseases 13

Application Every time you come back from the playground, your mother asks you to wash your hands and legs. Why is this so important? There is a famous saying: “Prevention is better than washing hands with soap cure.” The best way to protect our body from diseases is to prevent the disease-causing germs from entering our body. The easiest way to do that is to keep our hands and legs clean by washing them with soap. Let us now learn some more ways to protect ourselves from diseases: PREVENTION OF DISEASES that spread There are different ways of preventing the diseases that spread from one person to another. 1) Prevention of airborne diseases • Use a handkerchief while sneezing or coughing. • Wear a mask in crowded places. • Do not spit here and there. • Keep the doors and windows of the house open during mornings and evenings. This allows sunlight to come into the house. Sunlight can kill disease-causing germs. • V accinations are preventive medicines. They protect us from wearing masks many airborne diseases. Example: tuberculosis and measles 2) Prevention of diseases that spread through touch • Wash both hands with soap and water before and after eating. This will prevent diseases spread through touch. • W ash both hands and legs with soap and water after using the toilet. This will prevent diseases spread through touch. water purifier polio vaccination 14

3) Prevention of waterborne diseases • A void having sherbet, cold water, ice, ice cream and so on from the roadside shops. • We must drink clean water. Boiling water for 15–20 minutes kills most germs and makes it safe for drinking. These days we use water purifiers for purifying water. • V accination protects us from waterborne diseases. Example: polio, typhoid and hepatitis vaccines 4) Prevention of diseases spread by insects • Mosquitoes spread many harmful diseases like malaria, dengue and so on. Wearing full-sleeved clothes and full pants may prevent mosquito bites. Applying a mosquito repellent cream or lotion when you go out to play is important. Sleeping under a mosquito net is also a way to prevent mosquito bites. Mosquitoes lay eggs in stagnant water. We must ensure that there is no stagnant water in and around our neighbourhood. • H ouseflies cause diseases like typhoid and cholera. They carry germs from dirty places, dustbins and so on. They lay eggs in mosquito net moist, dark and dirty areas. So, we should keep our houses and surroundings clean and moisture free. Also, we should keep food items in closed vessels to prevent flies sitting on them. Have you seen a housefly rubbing its legs? Find out why it does so. PREVENTION OF DISEASES that do not spread healthy food To avoid diseases that do not spread, we should eat a balanced diet with all the nutrients in the required amounts. We should try to avoid eating junk food. We should eat freshly prepared food, milk and fruits. We should also exercise and play outdoor games. People who live in cities should wear special masks when they go outdoors to protect themselves from the dust and smoke in the air. Most importantly, we should stay relaxed and happy. Being worried about anything or being angry makes our body weak, which can make us sick easily. Diseases 15

In spite of taking all the care, if we suffer from any disease, we should go to the doctor. The doctor diagnoses the disease and gives medicines to treat it. exercising a doctor checking a patient Amazing Facts We have a system inside our body which protects us against disease-causing germs. When germs enter our body, this system attacks and kill those germs. It is like an army of soldiers that protects us from our enemies! Higher Order Thinking Skills (H.O.T.S.) So far we have discussed the diseases that affect few people at a time. Sometimes, some diseases affect a lot of people at the same time. They spread very quickly and are very difficult to control. These diseases cause great loss of human life. Such diseases are called epidemics. Examples of epidemics are smallpox, plague, yellow fever, malaria, SARS, Ebola, Zika virus epidemics and so on. Did you know that a lot of people die worldwide due to malaria? Find out the symptoms of this disease. With the help of your teachers and parents, put up charts in your school and neighbourhood about the practices needed to prevent malaria. 16

Lesson Keeping Our Neighbourhood 5 Clean Let Us Learn About R the different types of wastes. U disposal of waste. A the 3Rs – reduce, reuse and recycle. H compost. Think On the way to her aunt’s place, Reena saw four garbage bins near a bus station. They were of different colours. She wondered why they were of different colours. Why were there four bins instead of one? Remembering Every day, we throw away the things which we don’t need anymore. Things that are no longer useful to us are called waste. What are the unwanted things you throw away at school? Waste at school may include paper, chalk pieces, pencil shavings and so on. It may also include leftover food, fruit peelings, chocolate wrappers and plastic covers. In the same way, waste is generated at different places. Wastes are of three types. 1 Solid waste: They may be either wet or dry. Wet waste wet waste dry waste consists of kitchen waste such as vegetable and fruit peels and pieces, tea leaves, bones, fish scales, as well as cooked food. Dry waste consists of waste such as paper, plastic, metal, glass, rubber and so on. 17

Some solid waste rot when buried under the soil. This waste that decays waste that does decay of waste happens with the help of air, water and tiny organisms. The waste becomes part of the in the soil not decay in the soil soil. Example: cow dung, dry leaves, leftover food Some solid wastes do not decay when buried in the soil. Example: plastic bottles and bags, glass pieces 2 Liquid waste: Waste in the liquid 3 Gaseous waste: Waste in the form of gas form is known as liquid waste. is called gaseous waste. Example: smoke Example: wastewater from from vehicles and factories and many other houses and factories human activities liquid waste from households gaseous waste from factories, vehicles and firecrackers The waste generated in different places may differ. Waste from cities mainly includes paper, plastic bottles, glass pieces, kitchen waste and so on. Waste from villages mostly includes the waste from fields and farms. It can be in the form of animal waste such as cow dung, stalks of the harvested crops, dry leaves and so on. Understanding What happens if we litter our surroundings with garbage? Some waste will decay, and some will stink. Flies and worms will breed on the garbage. This may cause diseases to spread. Dry waste like broken pieces of glasses or nails can cause injury during handling. Waste materials are harmful and they also make our surrounding dirty. So, waste has to be disposed of carefully. The process of bins for waste disposal getting rid of the waste is called waste disposal. We must follow the following steps for easy waste disposal. 1) Sorting of waste material: We must sort waste into wet and dry waste. We must also sort waste based on their ability to decay in the soil. 2) Disposing of waste in different bins: We should dispose the sorted waste materials in separate bins. Bins of different colours and labels should be used. Do you know what happens to the waste after you sort it and dispose of in different coloured bins? 18

In some cities and villages, waste materials are collected from different places using garbage trucks. Trucks carry these waste materials to dumping yards. Some waste is burnt in big, oven- like machines. Some waste is buried in the soil, while other waste materials are reused to make some useful products. oven-like machine to burn waste materials In places where there is no garbage disposal system, people throw the waste in open fields. They may burn their household waste in their backyard. This makes the surroundings dirty unhygienic and polluted. Application Heaps of waste are collected every day in cities and villages. Getting rid of all this waste has become a difficult task. Burning waste and plastics causes air pollution. Burying plastic and other harmful waste in the soil will make the soil unfit for living things. This may also pollute the underground water. So, what can we do to manage our waste? Reduce, Reuse, Recycle (R3 or 3R's) The 3Rs is a method to manage waste correctly. Let us understand what the three R's mean. 1) Reduce: We should reduce or limit the use of things such as plastic bags that are harmful to the environment. 2) Reuse: We should reuse things as much as possible before replacing them. For example, we can donate some old clothes, toys or other items that are in good condition. The needy people can reuse them. 3) Recycle: Have you seen a person who collects old newspapers, bottles and boxes? What happens to this waste? We can make new useful things from such wastes. This is called recycling of the wastes. For example, old newspapers collected from houses are made into paper pulp. New items like paper cups and dishes are made from the pulp. Have you seen this sign anywhere? We use it to label materials which can be recycled. Sometimes a fourth R is added to the three basic ones, generally standing for either rethink or recover. Rethink means we should think of the impact of things we use, on the environment. Recover means we should practise creating new things from waste. We have seen how to manage the waste from the household. But we also recycle need to manage the waste from our body. Keeping Our Neighbourhood Clean 19

Some people defecate in the open. Do you think this is a good habit? What harm can it cause? Amazing Facts Paper is made from the wood of trees. If we recycle 1000 kg of paper, we can save around 17 trees from getting cut. Higher Order Thinking Skills (H.O.T.S.) We have seen that some wastes decay in the soil. Leaves and food form compost after few months of decaying. This compost provides nutrients for the plants and helps them grow. Let us learn how to form compost. 1) Dig a small pit in the backyard. A large-sized pot can also be used instead of a pit. 2) Put wet waste like fruit peels, vegetable waste, dry leaves and leftover food inside the pit. Chop larger pieces into small ones for easy decay. In villages, animal waste like cow dung is also added to compost pits. 3) Cover the waste with a layer of soil. 4) Spray some water to keep it wet. adding kitchen waste to compost pit 5) Keep adding layers of waste and soil for a month or so. 6) The lower layers will get changed into a black coloured compost. This compost is rich in nutrients that help in plant growth. It can be used in farms, fields or gardens to grow plants. compost 20

Inside the Lab - A Inside the Lab – A Make sure you do these activities only with the help of a teacher or an adult. Activity A1: Digestive System You will need: cardboard, brown paper, tubing or piping of six different sizes (refer to the picture), markers, stickers, adhesive materials (glue or tape), empty soft drink can, a plastic bottle (as shown in the picture), empty tetra pack juice carton, empty toothpaste tube You need to: liver mouth food pipe 1) paste the brown paper on the cardboard using glue or tape. 2) cut off the bottom half of the toothpaste tube. 3) stick the toothpaste tube (as mouth), the stomach plastic bottle (as liver), soft drink can (as the stomach) and juice tetra pack carton on the cardboard using glue or tape, as shown in the picture. 4) use rubber pipes of different sizes for the tubular organs such as the food pipe and large small intestine intestines. Also, cut one small piece of intestine rubber pipe to represent the anus. Once cut out, arrange them in proper order and position. Now, stick these pipes to the board using glue or tape. anus 5) label the organs in the digestive system using markers and stickers: mouth, food pipe, stomach, small intestine, large intestine, liver and anus. 21

Activity A2: Disease Prevention Charades You will need: chart paper, marker, paper box, mark sheet to mark the scores and a pair of scissors You need to: 1) divide the class into two teams – team A and team B. 2) let both the teams make disease prevention cards. 3) cut out small cards from the chart paper. 4) write various methods of prevention to keep us away from diseases. 5) put the cards inside the paper box and shuffle. 6) ask one student from team B to pick a card. The child should then act out the method of prevention mentioned in the card without using any words. For enacting one card, give a time limit of 2 minutes. 7) ask the other students from team B to guess what method of prevention is being enacted. 8) ask team A to check the time taken and write the scores on the mark sheet. 9) reverse the role. Now, team A will enact and team B will record the time. 22

Lesson Water Storage and Quality 6 Let Us Learn About R water storage – now and then. U water purification methods. A water pollution. H the effects of water pollution. Think Amit’s class teacher told the students that the class would be visiting the nearby dam the next day. She also said that the entire city got its drinking water from the dam’s reservoir. From where does the dam get the water in its reservoir? a dam and its reservoir Remembering We have learnt that rain is the main source of water. But, the rainy season in India lasts for three to four months. And we need water throughout the year. So, we need to store it for later use. How do we do that? Let us learn about the storage of water in detail. OLD WATER STORAGE SYSTEMS Several methods were used to store water in the earlier times. 23

1) Wells: People dug wells to store stepwell draw well groundwater (rainwater which seeps into the ground). The wells were of different types. Where the wells were shallow, people could draw water with a pot held in hand. Some were deep and needed steps or a bucket with a rope to draw water. Wells are both the source of water and the storage system. 2) Water tanks in the forts: Water tanks were dug to store water. 3) River bunds: Bunds were built across water tank in a fort bund across a river the rivers to store river water. NEW WATER STORAGE SYSTEMS 1) Dams: Dams are the most important water storage systems used in recent times, as well as in the days gone by. Dams are walls or barriers built across the Bhakra Nangal dam Nagarjunasagar dam rivers. These barriers create a large artificial lake. The lake stores huge quantities of water. The large artificial lake formed by a dam is called a reservoir. India has many large dams like the Bhakra Nangal, Nagarjunasagar, Sardar Sarovar and so on. 2) Borewells: Borewells are dug to draw out groundwater using pumps. They are deeper and narrower than the wells. 3) Water tanks: A water tank is a container for storing water. It is made of bricks, plastic or metal. water tanks 24

The water stored in some of these storage systems may not be clean enough to use for drinking or bathing directly. The water we use for drinking must be clean and safe. It should be free of dirt and germs. It should be free of any smell. Water that is safe to drink or to use for food preparation, without the risk of health problems is known as potable water. Understanding Even though rainwater is pure, while coming from the clouds to the Earth it gets dirty. Dust from the air gets mixed in the rainwater. While flowing over the ground, mud and other unhealthy things also get mixed with it. So, the water from different storages might contain dirt, soil and germs. How do we get clean drinking water? The water from different storages is purified. Water purification means removing all unwanted and unhealthy substances from the water to make it clean and safe for our use. The water from different water sources is taken to water purification centres through huge pipes. Water is purified there. This water is stored in big water tanks at a height or under the ground. Then, from these tanks, water is supplied to every household. water tank source of water water purification centre houses water supply to homes after purification Water Storage and Quality 25

This is the way to purify water in large amounts. How can we remove the impurities from water at home? Let us see different ways to purify water in small quantities. 1) W hen we keep muddy water to stand for some time, the mud and sand get settled at the bottom. Once the sand and mud settle at the bottom, we can pour the clear water into another vessel. This water is not fit for drinking. water sand and mud sand and mud clear water separating clean water from sand and mud 2) W hen we slowly pass water through a sieve or mesh called a filter, the sand and mud get stuck in the sieve. The water is still not safe for drinking. A thin cloth, clay, layers of sand, gravel and charcoal are some types of filters. different types of filters The above two ways remove the impurities from water. But they do not make the water fit for drinking. Even filters cannot remove the tiny impurities. Some methods to make water fit for drinking are: 1) Boiling water for 10 –15 minutes kills harmful germs in the water. It is the safest method of purification. 26

2) For a larger quantity of water, boiling is not possible. So a chemical alum called chlorine is added to the water to kill the germs. It is used to prevent the spread of waterborne diseases such as cholera, dysentery and typhoid. A chemical called alum is also used to purify water. Swirling some alum in water for some time and then filtering the water makes the water pure. Water purifiers we use today, can filter as well as purify the water and make it fit for drinking. Application You have learnt that the water in water bodies contains impurities. Do the water bodies contain only mud and sand? What are the other things which may get mixed with the water in the water bodies? Water bodies may become dirty because of the addition of the wastewater from households, factories and so on. This wastewater may contain many harmful substances. The addition of harmful substances to the water is called water pollution. The main causes of water pollution are as follows: water from a factory let out in the river 1) Waste from the factories is let out in the nearby rivers and lakes, causing pollution of water. 2) A lot of chemicals are used to grow plants on the farms. Some of them are used to increase the plant growth. Some are used to kill harmful insects. All these chemicals mix with the soil and then get into the underground water. This causes pollution of underground water. 3) In villages and small towns, domestic practices also pollute chemical sprayed in a farm water bodies. For example, washing clothes, cleaning utensils and bathing animals in the water bodies. This leaves the water body polluted with soap, dirt and waste. 4) Open defecation also bathing animals in a river contaminates our water sources. washing clothes in the river Water Storage and Quality 27

We learnt about water pollution and its several causes. Can you list out some of the remedies to prevent the sources of water from getting polluted? Amazing Facts The concept of building dams is as old as early human civilization. The Kallanai Dam, also known as the Grand Anicut, is the fourth oldest dam in the world. It still serves the people of Tamil Nadu, India. The dam was built by King Karikala Chola. Kallanai dam in Tamil Nadu Higher Order Thinking Skills (H.O.T.S.) Using polluted water can have several harmful effects. They are as follows: 1) Waterborne diseases like cholera, dysentery and typhoid are caused by harmful germs present in the water. 2) Poisonous chemicals in the water may cause damage to our internal organs. 3) Poisonous chemicals in the water may also lead to the death of water (aquatic) plants and animals. 4) Soaps, detergents and some chemicals used in farms to grow plants can increase the growth of aquatic plants. These plants spread very fast and cover the water surface. The water does not get enough oxygen leading to the death of fishes and other water animals. dead fish floating in polluted water a fish that is dead due to the water covered with plants growth of algae 28

Lesson Importance of Soil 7 Let Us Learn About R soil and the living things within the soil. u the importance of soil. a taking care of soil. h the difference between soil and sand. Think Salim was planting a flowering plant in his garden. He found some earthworms in the garden soil. He was afraid that they would harm his plant. What do you think? Are they harmful or helpful? Remembering soil The soil is loose material that lies on top of the land. It 29 has rocks, minerals, water and air. Soil also has living things and dead things in it. Living and dead things are called organic matter. When the plant and animal matter in the soil rot (decay), a dark layer of humus is formed on the soil. Humus makes the soil nutrient rich. The soil is important for life on the Earth.

Soil holds water and nutrients. So, it is the right place for plants to grow. Soil supports the roots and enables plants to stand above the ground to get light from the Sun. This helps the plants to grow as they get water, nutrients and light. Soil rich in minerals and nutrients is called fertile soil. It helps in the growth of plants. Many animals dig into the soil and make the soil their home. • Animals such as rabbits use the soil to make dens for sleeping and giving birth to young ones. • S mall animals like ants and den earthworms earthworms live most of their lives in the soil. Earthworms are important for improving the soil. This is because the holes they make allow air into the soil. The holes also let water go through. • Microorganisms like the fungi and bacteria also live in the soil. They eat the dead plants and animals. This broken down material becomes food for plants (nutrients). microorganisms in soil Understanding Soil plays an important role in supporting life on the Earth. There are many uses of soil. Let us discuss a few. 1)  A griculture: Soil is used to grow crops. It has nutrients needed for cultivation. 2) W ater storage: When there is rain, soil absorbs water. This water goes into a deeper layer of soil and is used by plants and trees to grow. This water is also available as ground water for drinking and cultivation. growing crops in the soil 3) Home for living things: The soil provides shelter for insects, reptiles and birds. It is necessary for even other activities like nesting, hatching of eggs and so on. 30

4) Building material: Soil is used for the construction of houses, buildings, roads and so on. Soil is also used for making pots, decorative articles, toys, idols and so on. a hut with a mud wall roof tiles bricks making pots Application What happens to the soil when it rains heavily or winds blow strongly? The soil is swept away. This washing or blowing away of the top layer of the soil due to strong winds and rain is called soil erosion. Some human activities like cutting of trees, farming, grazing of animals soil erosion and so on, also result in soil erosion. How can we prevent soil erosion? 1) The roots of plants hold the soil tightly together. So, by planting more and more plants, we can reduce soil erosion. Grass can also be grown to hold the soil. 2) Bunds can be built across the farms to prevent rainwater from bunds across the farm washing away the soil. waste dumped on soil Dumping of waste affects the quality of the soil. Using chemicals to grow crops also affects the quality of the soil. The addition of harmful wastes to the soil is called soil pollution. It makes the soil unfit for growing plants. It can have various ill-effects on plants, animals and human beings too. How can we prevent soil pollution? 1) We should use products which can be broken down easily by the microbes in the soil. For example, paper breaks down easily in soil but plastic does not. So, we should use paper bags and not plastic bags. 2) Use of harmful chemicals in farming activities should be avoided. 3) Before throwing the waste from industries and houses, it should be treated to prevent soil pollution. Can you think of some other measures to prevent soil pollution? Importance of Soil 31

Amazing Facts A small spoonful of soil may contain 5000–7000 types of bacteria. Higher Order Thinking Skills (H.O.T.S.) Have you ever observed the sand on seashores or river beds? How is it different from the soil we find in farms and fields? sand soil 32

Lesson Roots and Flowers 8 Let Us Learn About R roots and flowers. u functions of roots and flowers. a uses of roots and flowers. h seasonal flowers. Think Is it easier to pull out some grass than a tree from the soil? Do you know why? Remembering underground roots Plants around us are of different shapes and sizes. Most plants have five main parts; roots, stems, leaves, flowers and fruits. Let us 33 discuss about the roots and flowers in detail. ROOTS Root is the part of the plant that usually grows below the ground. There are two main types of roots – taproot and fibrous roots.

Taproot: This consists of a thick main root Fibrous roots: This consists of many thin and its branches. It grows downwards. The branched roots of almost the same branches grow sideways from the main root. size. Plants such as wheat, sugar cane Plants such as hibiscus and carrot have a and onion have fibrous roots. taproot. main root branches taproot fibrous roots FLOWERS Just like roots, we also see a variety in flowers. Flowers are the most colourful and attractive part of a plant. They differ in shape, size, colour and fragrance. hibiscus sunflower zinnia jasmine lotus thunder lily bottlebrush bougainvillea All flowers develop from buds. The buds vary in shape petals and size. Young buds are covered with green, leaf-like sepals. They protect the bud. sepals As time goes by, the bud becomes bigger. After a few bud and flower days, it opens up, to show the petals. Petals may be white or coloured. As the bud opens, the sepals curl back and remain at the bottom of the flower. 34

Understanding All plant parts perform different functions which help the plant to live and grow. Now, let us learn about the functions of roots and flowers. FUNCTIONS OF ROOTS 1) Hold the plant in the soil: Roots hold the plant in the ground and keep it upright. 2) Absorb water, nutrients and air: Roots absorb water, nutrients and air from the soil and then supply them to the plant. If the roots get damaged, the plant will die. 3) Store food: Plants like carrot, radish and turnip store food in their roots. FUNCTIONS OF FLOWERS Producing seeds is the main function of a flower. Most radish, beetroot, carrot and turnip of the flowers grow into fruits which contain one or more seeds inside. Application We have read about functions of roots and flowers. Now let us learn how they are useful for us. USES OF ROOTS 1 Food: Roots such as the carrot, beetroot, turnip and radish store food and nutrients. They are used as food. 2 Medicines: Roots of plants such as ginger and turmeric are used to make medicines. 3Protect the soil and help it to store water: Roots hold the soil and protect it from getting washed away by water. Moreover, they help the soil to absorb and retain rainwater. USES OF FLOWERS Like roots, flowers are also useful to us. Food: Some cauliflower Spice: Clove is cloves flowers such a dried flower as cauliflower bud used as are used as a spice. vegetables. Roots and Flowers 35

Medicine: Flowers such as the rose and Perfumes and soaps: Flowers such as the hibiscus are used to make medicines. rose, jasmine and lavender are used to make perfumes and soaps. Bouquets and decoration: Flowers are used to make garlands and bouquets. perfume soap They are also used to make floral carpets (rangoli). Colour: Saffron is used as saffron marigold zinnia food colour. Marigold and zinnia are used for making colours to dye clothes. Amazing Facts Some plants have roots which grow above the ground. In Banyan trees, roots arise from the branches and grow towards the ground. These roots penetrate the soil and support the branches. Higher Order Thinking Skills (H.O.T.S.) WHEN DO FLOWERS BLOOM? Seasonal flowers: Did you know, in some plants, flowering happens only in a specific season? In summer, we see the gulmohar, jasmine, lily and so on. In winter, we see the rose, chrysanthemum, dahlia and so on. gulmohar jasmine lily chrysanthemum Day and night flowers: Flowers bloom at different times of the day. Some flowers like the jasmine open during night. The flowers which open at night are usually white in colour. They have a very pleasant fragrance. Find out the reason. 36