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Piyush Ganeshiya

Science 4

M.Sc. Chemistry, B.Ed. PGT (DPS Sonepat)

HOLY FAITH INTERNATIONAL (P) LTD.

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The Hummingbird series of Primary Books from I to V are based on National Curriculum Framework (NCF) 2005 and the new Syllabi for classes at the Elementary Level.

In the guidelines some of the objectives of teaching the different subjects at primary stage are:

• to train children to locate and comprehend relationships between the natural, social and cultural environment;

• to nurture the curiosity and creativity of the child particularly in relation to the natural environment;

• to develop an awareness about environmental issues;

• to engage the child in exploratory and hands-on activities.

The Hummingbird series focuses on themes that allow for a connected and interrelated understanding to develop and trigger the child’s thinking in new directions. They connect knowledge to the child’s life outside the classroom and also provide an overall development of children.

The series comprises of textbooks on:

MATHEMATICS Children need to develop a positive attitude towards and a liking for Mathematics at the primary stage, along with the cognitive skills and concepts that they acquire. The content includes Mathematical games, puzzles and stories that help in making connections between Mathematics and everyday thinking.

ENGLISH An integrated approach to the teaching of language is of particular relevance at the primary level. The books address different skills of language, namely listening, speaking, reading and writing, which focus on across the curriculum approach through a variety of genres – poems, stories, role-plays and drama to develop the language skills creatively.

SCIENCE Science education should develop competence and encourage inventiveness and creativity. The textbooks incorporate activities, observation, experimentation and encourage an active approach to science, connecting it to the world around the child, rather than information based learning.

SOCIAL SCIENCE The textbooks provide the social, cultural and analytical skills required to adjust to an increasingly interdependent world. The focus of the books is on a conceptual understanding rather than lining up facts to be memorized.

ENVIRONMENTAL STUDIES Environmental Studies is a subject dealing with Man’s relation to his whole environment, viz. his surroundings, his home, his neighbourhood, his city or town, extending ever outward. The books contextualize the relevance of the subject and bring it to life.

The textbooks present the subjects in a clear, concise, logical and chronological manner. It is expected that this new series will inspire the children to analyse, demonstrate and transform their world view.

Preface

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UNIT I1. Plants on Earth 1-102. How Plants Make Food 11-20

CONTENT

UNIT II3. Animals on Earth 21-34 4. Animal Reproduction 35-45

UNIT III5. Teeth and Microbes 46-54

6. Internal Organs of Our Body 55-62

7. Food and Digestion 63-73

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UNIT IV8. Matter and its Three States 74-83

9. Force, Work and Energy 84-95

UNIT V10. Air, Water and Weather 96-107

11. Soil 108-116

UNIT VI12. Our Environment 117-129

13. Our Universe 130-140

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Plants on Earth 1

Plants on Earth1

Unit I Learning Objectives

Terrestrial plants Aquatic plants Plants of grass family Non-green plants Insectivorous plants

The earth’s surface is made of land and water. Land consists of mountains, rocks, valleys, plains, deserts, marshes and sandy beaches. Water is present in the form of rivers, lakes, ponds, seas and oceans. Plants are found almost everywhere on the earth: in cold snow-bound regions, in dry deserts, in wet marshy areas, etc. They have adapted themselves to survive in different areas. Adaptations are the changes that allow a plant or animal to live in a particular place. The place where a plant lives is known as its habitat.According to their habitat, plants are of two types.1. Terrestrial plants: which grow on land.2. Aquatic plants: which grow in water.

TERRESTRIAL PLANTS

All the plants which live on land are called terrestrial plants. Depending on the different types of climates and soils they grow, plants are of many kinds. On the basis of the type of soil and climate, the terrestrial plants can be categorized as follows:• Plants on hills and mountains• Plants in plains• Plants in hot and damp areas• Plants in marshes• Plants in deserts

Plants on hills and mountains

Most of the trees found in hilly areas are tall and thin to receive sunlight and bear leaves throughout the year. They are evergreen trees. Their leaves are needle-like and water proof. Instead of flowers these trees bear cones, hence they are also called coniferous trees. Pines, firs, deodars, spruce, etc., are examples of such trees. Spruce

Evergreen trees do not shed their leaves all at once. A few leaves are lost every year and new ones grow to replace them.

GO FACT

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2 Plants on Earth

trees are found in very cold places. Besides trees, small flowerless plants like ferns, mosses, lichens also grow in hilly regions.

Spruce treeFir treePine tree

Plants in plainsThe climate in plains is neither too hot as in deserts nor too cold as in hilly areas. Plains receive a moderate rainfall. The plants of plains have broad, lightweight leaves, so that they can capture a lot of sunlight to make food. The flat leaves help water vapour to evaporate and keep the tree cool during summers. The plants in the plains shed their leaves in winter to protect themselves from loss of water and get new leaves in the spring season. Mango, neem, pipal, sheesham, banyan, gulmohar, mulberry, etc., are some examples of such plants.

Mulberry treeBanyan treeMango tree

Take a walk in your school park during the winter. Make a list of trees that shed their leaves.

ACTIVITY Plants in plains

Plants in hot and damp areasThe plants of these areas have lots of leaves. But they do not shed their leaves in winters, so they remain evergreen. Plants like teak, rubber, pepper, coconut, etc., grow in such places.

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Plants on Earth 3

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Coconut treeRubber treeTeak tree

Plants in marshesIn marshy areas, the soil is sticky and clayey and has plenty of water. Such areas are also called swamps and the plants which grow in marshy areas are called mangroves.The roots of the plants growing in marshes are unable to get air as the soil is covered with water. So, the roots grow out of the soil to breathe. Such roots are called aerial or breathing roots. Sunderban mangroves are examples of such plants.

Giant sequoia trees can grow as tall as a 25-30 meter high. The oldest Gi-ant sequoia (also known as Californian Giant Redwood tree) is more than 2000 years old.

GO FACT

Sunderban mangroves

Plants in desertsDeserts are hot and dry. There is very little water in deserts. The plants which grow in desert areas are very different. They need very little water and can store food and water in their thick and fleshy stems or leaves. They use their stored food and water very slowly. The leaves of these plants are in the shape of sharp spines. Spines prevent the loss of water and thus plants retain water. The leafless plants conduct photosynthesis in their green stems. They have long roots that go deep into the ground to absorb water. Cactus, prickly pear, date palm, etc., some examples of plants in deserts.

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4 Plants on Earth

Date palmPrickly pearCactus

Visit a desert area and make a list of the trees found there.

ACTIVITY Plants in desert area

AQUATIC PLANTS

The plants which grow in water are called aquatic plants. They can be put in three groups:

• Floating plants

• Fixed plants

• Submerged (underwater) plant.

Floating plants

Floating plants float freely on the surface of water. These float because they are either light or small in size. They use the sunlight and carbon dioxide from the air to make their food. Some plants have air filled up in their stems to hold themselves up in the water. Duck weed, water lettuce and water hyacinth are some floating plants. These plants protect small water animals of the pond from the heat of the sun.

Water hyacinth Water lettuce Duck weeds

An aquatic plant having the biggest leaf is Victoria amazonica.

GO FACT

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Plants on Earth 5

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Fixed Plants

These plants remain fixed to the bed of the pond. The roots of these plant extend down to the bottom of the pond or river. They have long, hollow, flexible stems with broad and flat leaves that float on the surface of water. The leaves also have a waxy coating, so that water does not stick to them. They breathe through pores on the upper surface of the leaves. The common examples of fixed plants are water lily and lotus.

Lotus Water lily

Underwater Plants

These plants grow completely underwater. They have narrow ribbon like leaves with no pores. These leaves arise in clusters from the roots and have no stomata at all. They breathe through their body surface. These plants remove the carbon dioxide gas exhaled by the aquatic animals and clean the water. This is why we put such plants in aquariums. Pond weed, hydrilla and vallisneria are common examples of this type.

Pond weedVallisneriaHydrilla

PLANTS OF GRASS FAMILYThe plants of grass family grow in plenty, in places that are not too dry or not too wet. Cereals such as paddy, wheat, jowar, bajra, sugarcane and bamboo belong to the grass family of the plant kingdom.

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6 Plants on Earth

SugarcaneWheatPaddy

These plants are useful to us in many ways.

Uses of plants of grass family • The grass plants provide food for human beings and

animals. Wheat, rice, jowar, bajra, sugar and fodder are obtained from plants of the grass family.

• Bamboo is a useful grass plant which is used to make baskets, brooms, chairs, mats, curtains and toys. In many parts of India, especially in the north-eastern part these are used to prepare tasty dishes.

• Grass is used for packing.• Some plants of the grass family are used in preparing

medicines.• The roots of the plants help to check soil erosion.

NON-GREEN PLANTS

Some plants like mushrooms, toadstools, etc., do not have the green coloured pigment, chlorophyll. So, they cannot make their own food. They feed on dead and decaying matter. Due the absence of chlorophyll, these plants are called non-green plants. Mushrooms, moulds and yeasts are some examples of non green plants.

INSECTIVOROUS PLANTS

These are unusual plants that eat insects, though they make food by photosynthesis. These plants grow in a soil which is poor in minerals, so they trap and eat insects for extra nutrition. In venus flytrap, the leaf is folded into two halves.

Mushrooms

Paper was first made by the people of Egypt from a grass called Papyrus. That is why it is called paper.

GO FACT

Bamboo is not a tree but it is a grass.

GO FACT

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Plants on Earth 7

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When an insect sits on the leaf, the two halves get closed and the insect gets trapped. Leaf of pitcher plant is shaped like a pitcher with a lid. It is filled with nectar. When an insect comes to feed on the nectar, the plant trap the insect by closing the lid. Sundew plant catches insects on deadly hairs that cover their leaves. The sticky drops at the end of the hair trap the insect. All these plants catch insects and digest them and use the nutrients.

SundewPitcher plantVenus flytrap

KEYWORDS

Evergreen: having green leaves or needles all year.

Shed: to lose a natural covering by natural process.

Swamp: a seasonally flooded bottomland with more woody plants than a marsh and better drainage than a bog.

Clusters: to gather or grow into bunches.

Soil erosion: the washing away of soil by the flow of water or air.

Trap: to catch.

Nectar: a sweet liquid secreted by flowers of some plants.

SUMMARY

Plants are found everywhere on the earth.

Plants growing on land are called terrestrial plants. They are found on hills, in plains, in deserts and in marshy areas.

Plants growing in water are called aquatic plants. They can be floating, fixed or submerged.

Mushrooms are non green plants. They cannot make food and absorb food from outside.

Plants of grass family are useful to man in many ways.

Insectivorous plants eat insects.

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8 Plants on Earth

EXERCISES

Summative assessment

A. Multiple choice questions.

1. Which of the following plant do not have chlorophyll?

(a) Mango (b) Peepal

(c) Mushroom (d) Coconut

2. Which of the following is an insectivorous plant?

(a) Venus flytrap (b) Hydrilla

(c) Mushroom (d) Yeast

3. Which of the following is a flowering plant?

(a) Fern (b) Gulmohar

(c) Moss (d) Lichen

4. Water does not stick on the leaves of lotus plant due to

(a) long root (b) flexible stem

(c) flat leaf (d) waxy coating of leaf

5. The leaves of trees found in hilly areas are

(a) broad (b) needle like

(c) ribbon like (d) none of these

6. The main food that plants of grass family give us are

(a) medicines and fodder (b) wheat and rice

(c) straw and sugar cane (d) all of these

B. Fill in the blanks.

waxy, non green, terrestrial, adaptation, insect

1. The plants which live on land are called ___________ plants.

2. Changes that a plant make to survive in a particular surroundings are called ___________.

3. Floating plants have ___________ coating on their leaves.

4. Pitcher plant is an ___________ eating plant.

5. Mushroom is an example of ___________ plants.

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Plants on Earth 9

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C. Answer the following questions.

1. How are the plants in plains different from the plants in hilly areas?

2. How are some plants able to survive in desert areas?

3. What are aquatic plants? Give two examples.

4. A lotus plant grows in water. How does it adapt itself to live in water?

5. How are underwater plants useful?

6. Write some uses of grass family.

7. How does the pitcher plant trap insects?

Formative assessmentA. Match the following.

Column A Column B

Insectivorous plant Hydrilla

Plant in desert Mangroves

Underwater plant Duck weed

Non-green plant Venus flytrap

Plant in damp area Cactus

Plant in marshes Mushroom

Floating plant Rubber

B. True or false.

1. Aquatic plants are found in desert.

2. Mould and mushroom are insectivorous plant.

3. Pine trees have cones.

4. Coniferous trees have cones in place of leaves.

5. Duck weed and water lettuce are underwater plants.

C. Oral question.

1. What do fungi and mushroom feed upon?

2. Which adaptive features in conifers help them to survive in extreme cold and snow?

3. Why do floating plants have waxy coating on their leaves?

4. Name any two insectivorous plants.

5. Name any two plants grown in hot and damp area.

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10 Plants on Earth

Fun Zone

Guess who am I?

1. I am a flower offered in temple and my stem makes a tasty dish.

L __ t __ s

2. I am a plant but can eat insect.

V __ __ __ s __ __ y __ r __ p

3. I am an aquatic plant and can clean water.

H __ __ r __ __ l __

4. I am an evergreen plant, my fruits are commonly used as offering to god in temples.

C __ __ o __ u __

5. I am a desert plant, my leaves grow like thorns and I make my food in my green stem.

__ __ c __ __ s

Collective assessmentProject

Make a model of pitcher plant.

Humming Bird Science-4

Publisher : MBD GroupPublishers

ISBN : 9789351809715 Author : Piyush Ganeshiya

Type the URL : http://www.kopykitab.com/product/12302

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