Human society has reached a stage of prosperity, which was not

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1 the h e magical a g i l mysteries m y s t e r s of o f nature n a t u r e

2 A note from Dr R K Pachauri Human society has reached a stage of prosperity, which was not expected several decades ago. Yet, we have a large number of people living in poverty and barely able to keep alive. It appears that they have not been touched by human progress at all. At the same time, what we regard as progress has resulted in damage and destruction of our natural resources and caused serious problems such as human-induced climate change, which threatens all forms of life in the form of sea-level rise, heatwaves, floods, droughts, and melting of glaciers in different parts of the world. All of this provides a strong reason for us to change the way we have been pursuing human activities and what we have mistakenly believed as human progress. For instance, we must now use renewable sources of energy, eco-friendly methods of production and consumption, make efficient use of water in every activity, and protect biodiversity. It is in the hands of the children to try to change their own lives towards greater protection of the environment and all our natural resources. They can also take active part in changing the thinking of adults. Children can take a lead in organizing actions at the community level, which support conservation of resources, recycling of waste water, and greater use of renewable sources of energy. This series of children s books is aimed of providing children knowledge on what needs to be done in all these areas. I hope those who read these books will not only enjoy them greatly but also feel inspired to implement actions that are described in these pages, so that we create a beautiful, peaceful, and healthy future for the human race. R K Pachauri Director-General, TERI Chairman, Intergovernmental Panel on Climate Change

3 The Energy and Resources Institute

4 An imprint of The Energy and Resources Institute The Energy and Resources Institute, 2014 Published by TERI Press The Energy and Resources Institute Darbari Seth Block, IHC Complex, Lodhi Road, New Delhi , India Tel / , Fax: / India +91 Delhi (0)11 teripress@teri.res.in Website: ISBN All rights reserved. No part of this publication may be reproduced in any form or by any means without the prior permission of The Energy and Resources Institute. Author: Arshi Ahmad Publishing Head: Anupama Jauhry Editorial and Production Teams: Ekta Sharma, Himanshi Sharma, Pallavi Sah, Aman Sachdeva, Mahfooz Alam Design and Illustration Teams: Priyabrata Roy Chowdhury, Rajiv Sharma, and Vijay Kumar; Neeraj Riddlan Printed and bound in India This book is printed on recycled paper.

5 Contents How do plants make food? 6 How do plants store food? 8 How do plants breathe? 10 How do plants drink water? 12 How do plants protect themselves? 14 How do plants disperse their seeds? 16 How do plants reproduce? 18 How do fish breathe in water? 20 How does a caterpillar turn into a butterfly? 22 How do living creatures depend on each other? 24 How do animals protect themselves from enemies? 26 How do animals live in very hot and cold places? 28 How do animals sleep the winter away? 30 How do birds fly distances? 32 How are baby animals born? 34 How does day turn into night? 36 How do the seasons change? 38 How is lightning formed? 40 How does water go around in a cycle? 42 Fun with clues 44 Index 46

6 How do plants make food? What do you do when you feel hungry? You head to the kitchen and look for something to eat. Have you ever wondered whether plants also feel hungry? What do they eat? Who cooks for them? Well, plants do not eat like we do, but they prepare their own food. Recipe for plant food Plants use light energy from the Sun to prepare their food. They do this by a process called photosynthesis. Photosynthesis takes place in the leaves of green plants. So, the leaf is a plant s kitchen! All living things are made up of very small blocks called cells. The cells of leaves have chloroplasts. These contain a magic ingredient called chlorophyll, which gives green colour to the leaves. Without chlorophyll, there would be no photosynthesis and no food! 6-7 A plant that eats Some plants do eat, after all. The Venus flytrap is a plant that eats insects. It has nectar, a sweet liquid, to attract insects. Fine hairs on the edges of its leaves form a jaw-like trap. As soon as an insect enters the jaws of the flytrap, the trap closes. Cooking plant food Besides sunlight and chlorophyll, two more ingredients are needed for photosynthesis carbon dioxide and water. Leaves have tiny openings, or pores, called stomata on their surfaces. Carbon dioxide from the air enters the leaves through these pores. Water trapped in the soil travels to the leaves through the roots. Chlorophyll traps energy from the Sun. Using this energy, carbon dioxide and water combine to make glucose. Glucose is a kind of sugar. It is also plant food!

7 THAT S HOW THINGS HAPPEN carbon dioxide + water = sugar + oxygen Plenty of food, and oxygen too! All of us, humans and animals, depend on the food made by plants. Plants also give out oxygen into the air during photosynthesis. We all use this oxygen for breathing. Now you know why green plants are so important to us! Chlorophyll Breathing easy! Plants use chlorophyll in their leaves to trap sunlight, and together with carbon dioxide and water from their roots, they make sugar and oxygen. We can t cook! Not all plants can make food. Fungi are a group of non-green plants like mushrooms and moulds. They do not have chlorophyll and cannot make food. They absorb food from other living plants. Some get their food by breaking down dead animals and plants.

8 How do plants store food? Green plants are our food factories. They make more food than they use. They need warehouses to store the extra food. They store it in their roots, stems, leaves, and fruits. You will be surprised at the odd shapes that plant parts adopt to store food! Going underground! Stems hold plants erect. They enable water to travel from the roots to the leaves, and the prepared food from the leaves to all parts of the plant. Some stems grow underground to store food. Such swollen stems are also called tubers. Potatoes are examples of such stems. The eyes on a potato are buds, which can grow into new plants. Ginger, gladiolus, and crocus are also underground stems that store food. Swollen stems? 8-9 A radish is a root! Roots absorb water and support a plant. Sometimes, they change their shape to store food. Radish, carrot, turnip, beetroot, and sweet potato are actually roots! They are all swollen up to store food. You can also see fine root hairs on these vegetables.

9 THAT S HOW THINGS HAPPEN Leaves that turn into bulbs Photosynthesis and exchange of gases occur in leaves. They also store food and water. Bulbs, like onions, are modified underground leaves that store food. What we eat are fleshy scale leaves arranged one above the other in rings. The stem is reduced to a flat disc at the bottom of the bulb. Garlic and lily are also underground bulbs. Not a root, you said? That s root! Sweet fruits A fruit develops from a flower. It contains plant seeds, which grow into new plants. Tomato, peach, orange, apple, and mango are fleshy because of all the food they store. Some fruits may also be dry like peanut and oak acorn. Broccoli and cauliflower are flowers. The tree of life The baobab tree, commonly found in Africa, is also called the tree of life. People live in the hollows of its huge trunk. They eat not only the fruit (called monkey bread) but also the leaves, seeds and roots. The trunk stores hundreds of litres of water, which the tree uses during the hot summer.

10 How do plants breathe? Living things may be of different kinds, but they all have some things in common. One of them is that they all breathe. When we breathe, we take in oxygen and give out carbon dioxide. Plants also breathe in a similar manner. Do plants have lungs? Plants generally breathe through the stomata located on the leaves. An average leaf has about three hundred stomata in every square millimetre. That s a lot of stomata in a tiny speck of area! The Spanish oak tree has the largest number of stomata about 1,200 per square millimetre. Trees not only breathe through the stomata, but through pores on their trunks and branches as well. These pores are called lenticels. Glucose... my energy drink! How do plants get energy? Plants prepare food (glucose) with the help of sunlight. Plants breathe in oxygen, which helps break glucose into carbon dioxide and water. In the process, energy is released. This process is called respiration. Stomata Do plants respire all the time? Yes, plants respire all the time, while photosynthesis occurs only during the day. Respiration is the opposite of photosynthesis because when plants breathe, carbon dioxide is taken in and oxygen is given out. glucose + oxygen carbon dioxide +water + energy 10-11

11 How come? How so? That's how things happen: the magical mysteries of nature 35% OFF Publisher : TERI Press ISBN : Author : Arshi Ahmad Type the URL : Get this ebook