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WORKBOOK
natural science
Plants
Let's spea t What living things can yOJ see
in the pidtre? What season 1s it? What happens to many plants during thiS season'
r Do an experiment. You need: • Two empty yoghurt containers Wet cotton wool discs 4 dried beans Fill the cont•1n41rs wot h wet cotton wool discs
Put two beans into eKh container. Place them between the c.otton woold1scs. At the end of the un1t, you will find out what germinl!tion is
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Characteristics of plants
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A plant Is a livong tting with limited mobility. There lll'e many dofTerent types of plants All plants have one thong on common. they are loving ttings that make their own toOd
sool: meterool1n wh•ch plllntsarow
nutnenh: substllnces the! hvlna lhin85 need in ordor to grow
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vesSC!I: a tube which tr&nsports hqUidS
Plants need four substances to make theor own food water, mineral~. sunliahl and arbon dioxide, Plants get these substances using three main organs: roots, stems and leaves.
.··· ................. Fun f d l . leaves copture sunl'8hl and c"'bon
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d•oxode from the air. Then, they use the sun•atrt. Clrbon doa.lde. wat..lllld m•ner&ls to rmke nulroelts.
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·' Sequo1e tre.-s ore the oldest and • largest pl~~nts on Elrlh They cen grow over 75 metn>S toiiMd liVe for thousands of years. How IS th1s possoble> CM gllllll se quo< as evon resast fi,_.?
r Stems ~ eep th• pi MI upnght ond support rt. The trunl< of o tr•e IS o very thiCk stem. 1t
elso cernts wet.r, mln..-olsend nutnents to other ports of the plent through veuel•.
FI NAL TASK Check your
experiment. Put one yoghurt container in the frie4le andtheotheroneln a warm room. E~~ery two days,lfft up the cotton wool disc:; on the top and take photos
Roots enable plants to hlk111 wMfr end mene~ls from the SO< I. Some plants store nutr1ents
In lh e" roots.
Wn t e down the changes you observe, induding the temperature ot the fridge and room. Remember to keep the cotton wool wet'
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Classification of plants ~ r Non-flowering plants
Flowering plants
Non-flowering plants do not have seeds. They reproduce through spores. Spores are tiny cells that g ermrnate l!lnd grow rnto a new plant.
Flowering plants have organs like flowers. fruits and seeds that help them to reproduce.
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Anglo~perm~
F•rn~
Ftui1
Angiosper ms,likeapplet rees. areplantstl>atgrow fruit wrth seeds. The seeds .,.e located rnsidethe fruil
Ferns hi)ve roots. leaves and stems. f£1rn spores are formed on the underside of the leaves..
Gymno~pe rm~
Mosses Seed
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Gymnosperms. lik" prne trees, oro plonts that hove
Mosses do not havP roots. leaves or st ttms. Moss
seeds but do not hav" fruit. Pine nuts are seeds Insid e pine cones. A ~ne cone from a ptnt tree rs
spores are produced in capsules which are M-t he
end af the filement.
note fru1t. 1t IS ,e flowttr.
Listen to Anna and Wil l talk about the different k fnd of trees t hey have in their gardens. Copythetablein your notebook and complet e it .
apple tree
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pear tree
r pine trees
cherT)' tree
Frl'ar.nrol~flF AlgQI~II!>
G)'mlllrellll
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the plants are flowering or non-flowering plants. Q
Plant nutrition
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Photosynthesis
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Plants make their own nut rients through photosynthe:J~ During this process, plants ab>vrb caroondioxide and water WJth minerals and r->lo>a~p oxygen into the air This process takes place In green leaves during the day. Leaves absorb energy from sunlight through a green pigment called chlorophyll and use it to produce glucose and oxygen T
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abse The nutrients formed inside the leaves are called elabon~tad sap. 6 Phloem vessels are small tubes t hat transport elaborated sap all over the plant.
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Sexual reproduction in plants Rep
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S.xual reproduction takes place inside t l1e flow..- whentwo reproductive cells from t wo different plants come together. This generates a new plant that is similar to them. Flowers are the reproductive organs in m ost plants and have male and female reproductive organs.
Reproductive organs Corolla
) Mal~ oraan~
Female oraan~
The stamen is th~
The pistil is the fomelc
mall' reproduct•v tu~rs .
Bulbs are at the bottom of th• stem.. Th•y graw underground. BlAbs stor• nulnt>ntsfor tht plent. When plantod
on the ground. each bulbg1ves riSt> to a n•w plant. Gor1ot ond onoons are bulbs.
Rhizomes'"'" underground sterns that grow honzontelly. Nt>w
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plontsgrow from
tht>u st•ms. AsporDgUS and oros ptonts ar• rhiZomes.
I Will Is helping his father to prepare dimer They need some ingredients from their garden. They m~to~.
3 Vanilla fnuit is used to create chocolat e flavouring. A right B wrong C doesn't say
; Describe t he shape of vamlla .
..t. The vanilla ordlid usually grows in t ropical
Read the text and answer these questions in your notebook. Then, discuss them with
• What are the speoal climate cond•toons vamlla requires? _ What charactensi:Jcs do orchids have that help them wllh the Important funct1on of pollination?
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Are the following sentences 'Right' (A) or ' Wrong ( B)? If ther e is not enough information, choose 'Doesn't say' (C). Don't forget to write down the answers in your notebook.
and subtropical regions. A right B wrong c doesn't say s The vanilla plant f irst g rew in Penu. A right
B wrong
c doesn't say
Growing plants Andy works in a garden centre. He wants to grow plants. Andy did an experiment todiscoverthe best conditions for growing plants. First, he took f our pots with soil. He planted 10 seeds fn each one. Then, he pl!l each pot in places with different temperatures. He watered the pots everyday. Here are tl1e results of Andy's experiment look at the pictures and answer the quesii ons.
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3 1da)'S
j 3 1days
ttdoes11'1 germ1nate
Which weatherconditiQn did Andyt esi for in his experiment? light temperature humKhty look at the pots. The gladiolus seeds did not grow in two pots. Identify them. Describe the weather conditions for each one. What is the best t emperature to grow plants f asi? What is t he best temperatur e to g erminate more seeds?
Explain your a ns wers. smSaviadlg11ol corn ~, N n~" 'J How does temperature affect plants uowth?
...\ 31 da)'S lt doesn't germ•na1e
Let's work together: Germination
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You have lea m! all about plants. You have also collected information from your experiment on the aermln atfon of plants. Now, let's look at our results! Gather the photos and data from the experiment. Put t he photos in order. Then, fill in this chart to organise the dat a. Desaibe the sequence of photos to define the process. ''fllf'll •
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Jllrtr!A N
f'lTin,...; OKI!!ln only travel !>bout 200 meires. Most pr-oducers 11 ve here bec~>use they nted ~ght to c~ry oo.rl photosynth e sos. Most fish and manntt mommo.l5 hve h ere..
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The middle t.one os betwe•n 200 M d 1,000 metres. There IS very httle •&ht on thtszon e. • o photosynthesos Is n ot possoblo Plants do n ~ hve tn tlnzon.. but many
!Ish do. ~--
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The deepest zone •• b.low 1.000 metru . lh..-e rs no !Unbghl h l'fe, .a ol os tot oily dorlllllltiHl W!Rilll~
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ldentofy the consumer, the producer and the decomposer in a food chan that ind udes tuna, algae and sardines
Discuss with your partner: Why do marine producer organisms only live between the surface and 200 metres underwater? There are no producers in the deepest zones of the ocean. Elcplain how living things can live there.
smSaviadogotol com Playandos~more
about ecosystems ;md theordharactetistocs.
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How human beings change the environment @ Scientist s believe t hat life on Earth started at least t hree billion years ago. But our species, Homo sopi~ns, originat ed only 200,000 years ago. Let's look back in time and see how human activity has changed the planet .
10,000 yea rs ago, the human population was very small, with only ar ound two or three million people. Human activity didn't change the environment much. Humans hunted animals and collected fruits and seeds forsurvival.
2, 000 years ago, humans had big farms for plants and animals. The human population grew to 300 million because there was more food. Therefore, agriculture and fanning changed the ecosystem. Nowadays ...
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200 year• ago, the Industrial Revolution began and the human population started to explode. Waste from industry polluted the air, water and land.
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At the beginning of the 21" century, the human population was seven billion inhabitants. If we can't control human activity, we may destroy our planet. Many spedes of plants and animals will become extinct. Natural resources will disappear. Air will be t oo polluted to breathe. Water wm be too polluted to drink and land will become filled with rubbish. The solutionis to reduce the neptive effects our actions have on the environment.
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Fun factl .
l Depending on how often people use : public tre~nsport. ride l::icyde. wolk, recycle or plappearan~• ar breedlnd. a species affed
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Our well-being depends largely on the production of g oods, but produdng and consuming implies generating waste. Not all waste is property trea ted and much of it ends up invading our natural environment. We may think that sunlight and water action breaks it down very quickly, butthis is not true. For example, a can of soft drink may take 200 ~at yea rs to disappear, and a nappy .. .450 measurts can years! you thnk 01 to reduce was1e?
WhO Uvea In this pond? In one of his field trips, Will has observed the inhabitants of a pond and made the following drawing to represent them.
Copy the drawing in yrur notebook and complete t he gaps. What role does each type of organism play in the pond: producer, consumer or decomposer? In your notebook, create the food chain linking the organisms by arrows . All t he inhabitants of the pond depend on a process that you know well : photos ynthesf s. Indicate whi eh label corresponds to which letter of the draw•ng.
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Oxygen
Raw sap
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Upstream a factory has been built that discharges untreated waste into the water. This action is causing a high m ortality of frogs. Answer the following questions: • How does a decrease .n frogs affect the spoonbill? L, What will happen to the number of grasshoppers?
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The human body and interaction
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What are the boys in the picture doing? Do yOAJ think doing sports is healthy? Why? Do yOAJ do any sports? Which ones?
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At the end ofthis unit, you will discover how the human bocly
works and how we canpradisesporls even when some parts of our body don't work normally.
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The three vital functions
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All living things have one thing in convnon: they can carry out the three vital f unctions of nutrl11on, Interaction and reproduction.
corry out . to do or complete
something breaJ< dom1· broek int o small or
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nut1 I We need nutrition in order to keep our bodies working. Ther e are tour human body systems that enable us to carry out the vita I function of nutrition: the digestive syst em , the respiratory system, the drculatory system and the excretory system.
Thehumanbodysy.rtems --------------------------The dlaestlve system
,..... The re~plratory system
s1omach
T he digestive system breal s down the food we eat Into smeller
molecules tht ""en be poostlfe to cure
some 1ypes o1 blindness What part of the1onguo do we use to taste flavours>
•.. £,u;a/udhf4Wed- ·•· One African fru lt, the Synsepolum dulcificium, makes bitter or acid foods taste sweet. How jsthis possible? 1t contatns a substance called mtrac.ulln, and th1s substance stops the receptors on the tongue that det ect bott er and aad tastes fromworkong properly. The effect can last up t oan hour.
What
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partsof1he tyo do you
know?
T he lightest mate.riaJ What specl~c
prqlen•ttat m attord oycu know?
~t /tltlcim< You already know that the plastu: conta•ners we use everyday can be transformed •nto new conta1ners, and the reason why rt Is so •m port ant to recycle them But d•d you know that they can be transformed 1nto many otherth1ngs? Some factones have succeeded tnus•ngthese plast•cs As well"' pl,stlt. to make clothes. The whblothe• motarhh plastiG from the bottles con we ecyclll' can be transformed mto threads'
P:per
Is I. YtJy llpt rnuuit.J,Js.,\ lt? Butlf we put ~sheet of pope.r, whlc.h wt.Jg.bs about S g, on • ddtctte .flower, the flower would b ·' So reax. whtmlwio.l "" we su In tltt phowg--L? Jt is ~hone aer~•· a.ud ·"t'"'· to the lud J0 -..- . 1t Is a simllr.t ma.te.rioJ pencils. I t lS the llglnert ma.terlal !bar ex.lstr lt presen 1.. It Js lhout 3 700 tJm li&hter thr.n ptperl • es
~is. Is • very l?'portant discovery, becwoeJthu
peci.lJ properties thlt malce it very use!ul 1 lechooloiY· n
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A 1aboratory in space 'In the 1990's, we launched an ....-------~-=::"!!""-~ artifidal satellite that crbits Earth at an altitude of 400 km. This enormous satellite is called the lntemational Space Station. The astronauts there do many experiments on space and Earth, but also on matter and matenals. Th1s research improves the materials we use •nour lives, and is used tomakemedtcallnstruments, for example. ~not proporun dau g!au have ,
Ano Wl)cd?
The wind chiU factor
lhe tempera!Ure Is 3 •c. btA the ..!nd chil ls
With the same t emperature, some days we feel colder than others . This is due t o the wind chill factor, which is the feeling of hot or cold a person f eels.
\ aady for us to use wh en we need it. The food w e eat is also a store of energy for our bod1es.
H ow much has t h e chemiCc:~l energy a pt>rso1, con sumes mcreesed? Whet do you thmk th1s mcrl!llse 1n energy IS due to?
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We u n tron~po-1 llllfi Y We C-c3 cna.t:?;
c ~~ter ..,d go~~rci&os. To >lq>otftcm. co!IO>p5i ,.,g, O> solid structure ,...., built