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ScienceScience

7Class

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CONTENTS

• Syllabus

1. Nutrition in PlantsWorksheets 1 & 2

2. Nutrition in AnimalsWorksheets 3 & 4 17 - 24

3. Fibre to FabricWorksheets 5 & 6 25 - 32

4. HeatWorksheets 7 & 8 33 - 40

5. Acids, Bases and SaltsWorksheets 9 & 10 41 - 48

6. Physical and Chemical ChangesWorksheets 11 &1 2 49 - 56

7. Weather, Climate and Adaptations of Animals to ClimateWorksheets 13 & 14 57 - 64

8. Winds, Storms and CyclonesWorksheets 15 & 16 65 - 72

9. SoilWorksheets 17 & 18 73 - 80

10. Respiration in OrganismsWorksheets 19 & 20 81 - 88

11. Transportation in Animals and PlantsWorksheets 21 & 22 89 - 96

12. Reproduction in PlantsWorksheets 23 & 24 97 - 104

13. Motion and TimeWorksheets 25 & 26 105 - 112

14. Electric Current and Its EffectsWorksheets 27 & 28 113 - 120

15. LightWorksheets 29 & 30 127 - 128

16. Water : A Precious ResourceWorksheets 31 & 32 129 - 136

17. Forests : Our LifelineWorksheets 33 & 34 137 - 144

18. Waste Water StoryWorksheets 35 & 36 145 - 152

• Solved Sample Paper (Term 1) 153 - 156

• Solved Sample Paper (Term 2) 157 - 160

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(iii)

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PREFACEYear after year CBSE has been introducing changes in the curriculum of various classes.

We, at Oswaal Books, closely follow every change made by the Board and endeavor to equip every student with the latest study material to prepare for the Term Examinations.

The latest offering from us are these Worksheets. These aim at providing comprehensive practice material for every chapter to ensure that every concept is revised in totality. These are prepared by experienced teachers who have translated their expertise into making these worksheets a wholesome study package. Every worksheet contains a mix of questions, for which the maximum marks and time are mentioned to create an exam oriented study material.

Our worksheets strictly follow the NCERT curriculum and include the following:

• Chapter-wise pullout worksheets with space for writing answers

• Synopsis of the important points from every chapter

• Wide variety of questions based on Summative & Formative Assessment

• Sample Question papers for Term 1 & Term 2

We feel happy to add these to our existing portfolio of Question Banks and Sample Question Papers. We hope that with our Worksheets, every student will discover a more interactive way of studying and thereby excelling in his examinations. We welcome any suggestions that come our way for improvisation.

We wish you good luck for the forthcoming academic year!!

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Science, Class-VII

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( v )

1. FoodFood from whereHow do plants get theirfood?

Utilisation of foodHow do plants and ani-mals utilise their food?

2. MaterialsMaterials of daily useDo some of our clothescome from animalsources?Which are these ani-mals?Who rears them?Which parts of the ani-malsyield the yarn? How isthe yarn extracted?What kinds of clotheshelp us to keep warm?What is heat?What is the meaning of‘cool’/‘cold’ and ‘warm’ ‘hot’?How does heat flow from/to our body to/ from thesurroundings?

Different kinds of ma-terialsWhy does turmeric stainbecome red on applyingsoap?

How things change/ re-act with one anotherWhat gets deposited on atawa/khurpi /kudal ifleftin a moist state?Why does the exposedsurface of a cut brinjalbecome black?

(Periods - 22)

Need for light, green leaffor photosynthesis, look-ing at any saprophyte/parasite and noting differ-ences from a green plant.

Effect of saliva on starch,permanent slide ofAmoeba.Role play with children.

(Periods - 38)Collection of differentsamples of woollen andsilk cloth. Activities to dif-ferentiate natural silk andwool from artificial fibres.Discussion.

Experiment to show that‘hot’ and ‘cold’ are rela-tive. Experiments toshowconduction, convectionand radiation.Reading a thermometer.

Testing solutions of com-mon substances likesugar, salt, vinegar, limejuice etc. with turmeric,litmus, china rose.Activity to showneutralisation.

Experiments involvingchemical reactions likerusting of iron,neutralisation (vinegarand baking soda), dis-placement of Cu fromCuSO4 etc.Introduce chemical for-mulae without explainingthem.

Autotrophic and het-erotrophic nutrition;parasites, saprophytes;photosynthesis.

Types of nutrition, nutri-tion in amoeba and hu-man beings, Digestive sys-tem – human, ruminants;types of teeth; link withtransport and respiration.

Wool, silk – animal fibres.Process of extraction ofsilk; associated healthproblems.

Heat flow; temperature.

Classification of sub-stances into acidic, basicand neutral; indicators.

Chemical substances; inachemical reaction a newsubstance is formed.

Coleus or any other plantwith variegated leaves,alcohol, iodine solution,kit materials.

Model of human teeth,charts of alimentary ca-nal, types of nutrition etc.,chart and model ofamoeba. The story of thestomach with a hole.

Samples of wool and silk;brief account of silkwormrearing and sheep breed-ing.

Potassium permangan-ate, metal strip or rod,wax, common pins, spiritlamp, matches, tum-blers,Thermometer etc.

Common substances likesugar, salt, vinegar etc,test tubes, plastic vials,droppers, etc.

Test tubes, droppers,common pins, vinegar,baking powder, CuSO4,etc.

Questions Key Concepts Resources Activities/Process

Science Syllabus - Class VII

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( vi )

Why is seawater salty? Isit possible to separatesaltfrom seawater?

3. The World of theLiving

Surroundings affectthe livingWhy are nights cooler?How does having wintersand summers affect soil?Are all soils similar? Canwe make a pot with sand?Is soil similar when youdig into the ground?What happens to waterwhen it falls on the ce-mented/ bare ground?

The breath of lifeWhy do we/animalsbreathe? Do plants alsobreathe? Do they also re-spire? How do plants/ani-mals live in water?

Movement of substancesHow does water move inplants? How is foodtransported in plants?Why do animals drinkwater? Why do we sweat?Why and how is thereblood in all parts of thebody? Why is blood red?Do all animals haveblood?What is there in urine?

Multiplication in plantsWhy are some plantparts like potato, onionswollen – are they of anyuse to the plants? Whatis the function of flowers?How are fruits and seedsformed? How are theydispersed?

Substances can be sepa-rated by crystallisation.

Climate, soil types, soilprofile, absorption of wa-ter in soil, suitability forcrops, adaptation of ani-mals to different cli-mates.

Respiration in plants andanimals.

Herbs, shrubs, trees;Transport of food andwater in plants; circula-tory and excretion sys-tem in animals; sweat-ing.

Vegetative, asexual andsexual reproduction inplants, pollination -cross, self pollination;pollinators, fertilisation,fruit, seed.

Urea, copper sulphate,alum etc, beaker, spiritlamp, watch glass, plate,petridish etc.

Data on earth, sun – size,distance etc, dailychanges in temperature,humidity from the news-paper, sunrise, sunsetetc.

Lime water, germinatingseeds, kit materials.

Twig, stain; improvisedstethoscope; plastic bags,plants, egg, sugar, salt,starch, Benedicts solu-tion, AgNO3 solution.

Bryophyllum leaves, po-tato, onion etc.; yeastpowder, sugar.

Making crystals of easilyavailable substances likeurea, alum, copper sul-phate etc. using super-saturated solutions andevaporation.

(Periods - 42)Graph for daily changesin temperature, daylength, humidity etc.;texture of various soilsby wetting and rolling;absorption / percolationof water in different soils,which soil can hold morewater.

Experiment to showplants and animals re-spire; rate of breathing;what do we breathe out?What do plants ‘breathe’out? Respiration in seeds;heat release due to respi-ration. Anaerobic respi-ration, root respiration.

Translocation of water instems, demonstration oftranspiration, measure-ment of pulse rate,heartbeat;after exerciseetc.Discussion on dialysis,importance; experimenton dialysis using eggmembrane.

Study of tuber, corm,bulb etc; budding inyeast; T.S./ L.S. ovaries,w.m.pollen grains; com-parison of wind polli-nated and insect polli-nated flowers; observingfruit and seed develop-ment in some plants; col-lection and discussion offruits/seeds dispersed bydifferent means.

(Periods - 16)

Questions Key Concepts Resources Activities/Process

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( vii )

4. Moving Things,People and Ideas

Moving objectsWhy do people feel theneed to measure time?How do we know howfast something is mov-ing?

5. How Things WorkElectric current andcircuitsHow can we conve-niently represent anelectric circuit?Why does a bulb get hot?

How does a fuse work?

How does the current ina wire affect the direc-tion of a compassneedle?What is an electromag-net?

How does an electric bellwork?6. Natural PhenomenaRain, thunder andlightningWhat causes storms?What are the effects ofstorms?Why are roofs blown off?

LightCan we see a source oflight through a benttube?

Observing and analysingmotion (slow or fast) ofcommon objects on land,in air, water and space.Measuring the distancecovered by objects mov-ing on a road in a giventime and calculatingtheir speeds. Plotting dis-tance vs. time graphs foruniform motion. Mea-suring the time taken bymoving objects to covera given distance and cal-culating their speeds.Constancy of time periodof a pendulum.

Drawing circuit dia-grams.

Activities to show theheating effect of electriccurrent.Making a fuse.

Activity to show that acurrent-carrying wire hasan effect on a magnet.

Making a simple electro-magnet.Identifying situations indaily life where electro-magnets are used.Demonstration of work-ing of an electric bell.

(Periods - 24)

Making wind speed andwind direction indicators.Activity to show “lift” dueto moving air.Discussion on effects ofstorms and possiblesafety measures.

Observation of the sourceof light through a straighttube, a bent tube.

Appreciation of idea oftime and need to mea-sure it.Measurement of time us-ing periodic events.Idea of speed of movingobjects – slow and fastmotion along a straightline.

Electric circuit symbolsfor different elements ofcircuit.Heating effect of current.

Principle of fuse.

A current-carrying wirehas an effect on a mag-net.

A current-carrying coilbehaves like a magnet.

Working of an electricbell.

High-speed winds andheavy rainfall have disas-trous consequences forhuman and other life.

Rectilinear propagationof light.

Daily-life experience;metre scale, wrist watch/stop watch, string etc.

Recollection of earlier ac-tivities. Pencil and paper.

Cells, wire, bulb.

Cells, wire, bulb or LED,aluminium foil.Wire, compass, battery.

Coil, battery, iron nail.

Electric bell.

Experience; newspaperreports.Narratives/stories.

Rubber / plastic tube /straw, any source oflight.

Questions Key Concepts Resources Activities/Process

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( viii )

How can we throw sun-light on a wall?

What things give imagesthat are magnified or di-minished in size?

How can we make acoloured disc appearwhite?

7. Natural ResourcesScarcity of waterWhere and how do youget water for your do-mestic needs? Is itenough? Is thereenough water for agri-cultural needs? Whathappens to plants whenthere is not enough wa-ter for plants? Wheredoes a plant go when itdies?

Forest productsWhat are the productswe get from forests? Doother animals also ben-efit from forests? Whatwill happen if forests dis-appear?

Waste ManagementWhere does dirty waterfrom your house go?Have you seen a drain?Does the water stand init sometimes? Does thishave any harmful effect?

Reflection, certain sur-faces reflect light.

Real and virtual images.

White light is composedof many colours.

Water exists in variousforms in nature.Scarcity of water and itseffect on life.

Interdependence ofplants and animals in for-ests. Forests contributeto purification of air andwater.

Sewage; need for drain-age/sewer systems thatare closed.

Glass/metal sheet/metalfoil, white paper.

Convex/concave lensesand mirrors.

Newton’s disc.

Experience; media re-ports; case material.

Case material on forests.

Observation and experi-ence; photographs.

Observing reflection oflight on wall or white pa-per screen.Open ended activities al-lowing children to ex-plore images made by dif-ferent objects, and re-cording observations.Focussed discussions onreal and virtual images.Making the disc and ro-tating it.

Discussions.Case study of people liv-ing in conditions of ex-treme scarcity of water,how they use water in ajudicious way.Projects exploring vari-ouskinds of water resourcesthat exist in nature in dif-ferent regions in India;variations of water avail-ability in different re-gions.

Case study of forests.

Survey of theneighbourhood, identify-ing locations with opendrains, stagnant water,and possible contamina-tion of ground water bysewage.Tracing the route of sew-age in your building, andtrying to understandwhether there are anyproblems in sewage dis-posal.

Questions Key Concepts Resources Activities/Process

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P-9

SUMMATIVE-ASSESSMENT

1 NUTRITION IN PLANTS WORKSHEET-1

Name ....................................................... Class............. Roll No.........Time

1.5 Hrs.

Max.Marks

50

MarksObtained

N TI N P L ANOITI SRTUN

LET’S REVISE

Nutrition : It is the process of obtaining nutrients from the environment. It is an importantsource of energy for growth and development of body.

Modes of nutrition :

(A) Autotrophic nutrition : Organisms synthesize their own food with the help of rawmaterials. Example—all green plants.

(B) Heterotrophic nutrition : Organisms derive energy (nutrition) from the food preparedby plants. Example—All animals, bacteria, and fungi.

Autotrophic nutrition : Green plants prepare their food by the process of photosynthesis.Photosynthesis is the process of synthesizing food from CO2 and water in the presence ofsunlight. Leaves are the sites for the synthesis of food. The green pigment called chlorophyllis present in leaves. Chlorophyll traps solar energy, which is used to prepare food from CO2

and water.

Sun is the ultimate source of energy. Green plants absorb CO2 from atmosphere through tinypores called stomata. Stomata are present on the surface of leaves.

Water and minerals are absorbed from soil and are transported to leaves via tiny vessel-likestructures present in roots.

Chlorophyll, sunlight, CO2 and water are essential raw materials for photosynthesis.

Carbohydrates such as starch and oxygen are the product of photosynthesis. Algae containchlorophyll and prepare its own food by the process of photosynthesis.

Heterotrophic nutrition in plants :

(A) Cuscuta (Amarbel) is a parasite, which obtains food from host plant.

(B) Pitcher plant is an insectivorous plant (insect-eating plant). Its leaf gets modified into apitcher-like structure, which traps the insects. It has both autotrophic and heterotrophicmode of nutrition.

(C) Fungi are saprotrophs. They obtain nutrition from dead or decaying organic matter.

(D) Lichens are organisms formed by a symbiotic relationship between algae and fungi. Inlichens, algae provide food to fungi while fungi absorb water and nutrients for algae.

Manures fulfill the nutrient requirement of plants.

A bacterium, called Rhizobium, fixes atmospheric nitrogen and converts it into a useable formfor the plant. It shows symbiotic relationship with the plant.

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Oswaal CBSE CCE Pullout Worksheet ForClass 7 Term I and II (2014) Science

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