FOOD AND NUTRITIONHave you ever wondered why you grow tall or fat, why you fall sick, how your wounds get healed etc…? All these happen because of the food you eat. Why do we need food?Have you seen a car or bike going on the road? How far does it go? Of course it will go on as long as there is petrol in it. So a vehicle needs petrol for its proper functioning. In the same way our body also needs some source for its proper functioning and that is the FOOD we eat. Only if we take in food our body can go on and on. Otherwise we will feel tired and cannot work properly.Show pictures of a car and a human bodyShow pictures of plant, lion, cow, crow Not only human beings but all living organisms including the small germs , plants and animals, all require food according to their needs. We need food mainly for:EnergyGrowth and repairProtection from diseasesMaintenance of the body systemsHence food can be divided into :Energy giving foodAfter a long and tiresome game of cricket what would you like to have first? Of course something that removes the tiredness from you. You became tired because your energy had gone low. When you take some glucose you feel energetic again. Hence rice, wheat, sugar, potatoes, bread etc. are all giving us energy. These food items contain CARBOHYDRATES which are packets of energy.Also ghee, butter, cheese, oils etc. give us energy because they all contain FATS which are a bit heavier packets of energy. Pictures of rice, potatoes, bread, cakePictures of butter, cheese, oil in a canBody building foodHave you checked your height and weight regularly? Is it always the same? No, we all keep growing until the age of 20 years. The food we eat should be rich in PROTEINS which help us in growth. When we fall we may get hurt and blood can ooze out. But after a few days we see that the wound is slowly healed and that area of wound has no more pain. This is mainly done by the proteins in the body. Food like pulses, eggs, milk, meat, soya are all rich in proteins.Pictures of fish, chicken, eggs, milk, soyaProtective foodAll of us fall sick at times. When you get cold and fever you recover after a few days even without medicines. This is mainly done by the VITAMINS and MINERALS in our body. Our body needs only small amounts of vitamins and minerals. There are different types of vitamins- A, B, C, D, K .Minerals are iron, calcium etc. Pictures of fruits and vegetablesOur body also needs water in sufficient amounts to keep the system clean.BALANCED DIETWe must eat all types of food in correct quantities. Otherwise we will become weak and diseased. A food that contains all the NUTRIENTS such as carbohydrates, proteins, fats, vitamins, minerals and water in the correct quantities is termed as a BALANCED DIET.Picture of a table with all food items shown aboveSometimes we see children having bleeding gums, or a thin and weak body or bent legs etc. What could be the reason for this? This is mainly because they may not be eating a balanced diet. Their diet could be having some nutrients in less or no quantity. When the body does not get a particular nutrient in the required quantity, it is said to be DEFICIENT in that nutrient. This can result in deficiency diseases in that person.A few examples of deficiency diseases are as follows:Scurvy – deficiency of Vitamin CPicture of a child with bleeding gumsAnaemia - deficiency of IronGoitre – deficiency of IodinePicture of a man with swollen neckWe have to take a balanced diet to keep ourselves healthy and free from diseases. NUTRITIONThe process of taking in food is termed NUTRITION.It is different in different living organisms. You may have seen that a cat likes to drink milk. While a cow eats grass and leaves, a lion eats other animal’s flesh etc. This is because they have different living conditions and body requirements.Picture of cow eating grass, lion eating flesh, man eating appleSome living organisms can prepare their own food, e.g green plants. Some depend on others for their food, e.g all animals. Some organisms live on the dead and decaying substances, e.g. bacterias in the soil. Hence we can divide the whole living organisms into three groups – producers (plants), consumers(animals) and decomposers(bacterias).Picture of plantPicture of cowPicture of bacteriasHave you ever wondered why all the plants are green in colour? Green plants have a substance called CHLOROPHYLL in their leaves that gives the green colour to the leaves.Plants are able to make food with the help of chlorophyll. For this they require mainly three items:WaterCarbondioxideSunlight The chlorophyll helps the plants to absorb the energy from the sun. The water absorbed by the roots is taken to the leaves. Carbondioxide is taken into the leaves directly. Hence food is prepared by the plants using all the above mentioned items. The process of preparing food by plants is termed PHOTOSYNTHESIS. So plants are also called as PRODUCERS or AUTOTROPHS.Picture of plant with photosynthesisBut animals do not have this green pigment, chlorophyll. So they cannot prepare their own food. They have to eat what the plants prepare. So all the food items like rice, wheat, fruits, vegetables are all given to us by plants. Since animals consume or eat what plants make they are called as CONSUMERS or HETEROTROPHS. A cow, a lion and a dog- all are animals and consumers. But what is the difference in the food they consume? A cow eats only plants, a lion eats only animals and a dog eats both plants and animals. Hence animals can be divided into 3 types according to the food they eat:Plant-eating animals or HERBIVORE – Cow, goat, elephantFlesh-eating animal or CARNIVORE – lion, tigerBoth plant and flesh eating animal or OMNIVORE – man, dog, foxPictures of different animals NEW WORDS(All the words in capital letters in the chapter can be taken as new words)EXERCISESFill in the blanks:We need -------------- to do work.Food rich in -------------------- gives us energy. -------------- is rich in Vitamin C.Food having all the nutrients in the right amount is called --------------------.------------------ is a carnivorous animal.Match the following:Cow scurvyAnaemia fleshVitamin C grassLion ironAnswer the following:What is a balanced diet?What gives green colour to the plants?Give three examples of herbivores.What causes bleeding gums?How can we prevent diseases?Give two examples of fruits rich in Vitamin C.Why should we take balanced diet?Is fox a herbivore?Give an example of protective food.What is photosynthesis?ActivityCollect pictures of different animals and paste it on a chart as herbivore, carnivore or omnivore.Go to a zoo and see what the different animals eat.Collect or draw pictures of the different types of food and list it on a chart as carbohydrates, fats, proteins, vitamins, minerals etc.Draw the picture of a healthy child and a diseased child.