Transportation in animals and plants CLASS VII

NCERT CLASS 7 SCIENCE Transportation in animals and plants
Owner: Deepa Unnikrishnan

1. TRANSPORTATION IN
ANIMALS AND PLANTS
CLASS 7
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Deepa Unnikrishnan

2. CIRCULATORY SYSTEM
Thecirculatorysystemisatransport
systeminthehumanbodywhichconsists
ofanetworkofbloodvesselsthatsupplies
food,water,oxygenthroughoutthebody
andremoveswasteproductsfromthebody.
Themainpartsofthecirculatorysystem
are:
oBlood
oBloodVessels
oHeart 2Deepa Unnikrishnan

3. COMPONENTS OF BLOOD
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Deepa Unnikrishnan

4. COMPONENTS OF BLOOD
1.Red Blood Cell (RBC)
2.White Blood Cells (WBC)
3.Platelets
4.Plasma
4Deepa Unnikrishnan

5. BLOOD
•Blood transports substances in the body. It has a
fluid part called plasma and cells like red blood
cells (RBC), white blood cells (WBC) and
platelets.
•Red blood cells :-contain a pigment called
haemoglobin which transports oxygen.
•White blood cells :-fights against germs and
protects us from diseases.
•Platelets:-help in clotting of blood.
•Plasma :The fluid part of the blood
5Deepa Unnikrishnan

6. HAEMOGLOBIN
•Haemoglobinbind with oxygen and transports
it to all the parts of the body and ultimately to
all the cells. It will be difficult to provide oxygen
efficiently to all the cells of the body without
haemoglobin. The presence of haemoglobin
makes blood appear red.
6Deepa Unnikrishnan

7. Blood Vessels
•Ourbodycontainstube-likestructurescalledthebloodvesselsthat
helpinthetransportationofbloodthroughoutourbody.
•Ourbodycontainsthreetypesofbloodvesselsbasedonthe
functionthattheyperform:
1.Arteries
2.Veins
3.Capillaries
7Deepa Unnikrishnan

8. Arteries
These blood vessels carry blood from the heart that contains oxygen
into different parts of the body.
Arteries have thick walls as the blood pressure is quite high in these
blood vessels.
They are narrow so that the blood can flow quickly through them.
They do not contain valves as the blood in arteries always flows in the
right direction due to the pumping of the heart.
8Deepa Unnikrishnan

9. Pulmonary Artery
•Thepulmonaryarteryisaspecialbloodvessel
thatconnectsthehearttothelungs.Ittakes
bloodthatcontainslessoxygen(deoxygenated
blood)fromthehearttothelungs.Hence,itis
unlikeallotherarteriesthatcarryoxygen-rich
blood.
9Deepa Unnikrishnan

10. Veins
•These blood vessels carry blood that is rich
in Carbon dioxide from the body organs to
the heart.
•Veins do not have thick walls as the blood
pressure is quite low in them.
•They are slightly wider than the arteries.
•They contain valves that prevent blood from
flowing in opposite direction.
10Deepa Unnikrishnan

11. Pulmonary Vein
•ThePulmonaryveinisaspecialbloodvesselthat
connectsthelungsandtheheart.Itcarries
oxygen-richbloodfromthelungstotheheart.
Hence,itisunlikeallotherveinsthatcarry
oxygen-lessblood.
11Deepa Unnikrishnan

12. Arteries Veins
These blood vessels carry blood from
the heart that contains oxygen into
different parts of the body.
These blood vessels carry blood that is
rich in Carbon dioxide from the body
organs to the heart.
Arteries have thick walls as the blood
pressure is quite high in these blood
vessels.
Veins do not have thick walls as the
blood pressure is quite low in them.
They are narrow so that the blood can
flow quickly through them.
They are slightly wider than the arteries.
They do not contain valves as the
blood in arteries always flows in the
right direction due to the pumping of
the heart.
They contain valves that prevent blood
from flowing in opposite direction.
12Deepa Unnikrishnan

13. Capillaries
•Smallbloodvesselsarecalledcapillaries.The
arteriesdividethemselvesintocapillarieswhich
thendeliveroxygenatedbloodtothetissuesin
thebody.Thenthesecapillariestakeupthe
deoxygenatedbloodfromthetissuestothe
veins.
13Deepa Unnikrishnan

14. Pulse And Pulse rate
•The continuous pumping of
blood in the arteries results in
rhythmic throbbing movements
which is called Pulse.
•Pulse rate is defined as the
number of pulse beats per
minute. The normal pulse rate
of human beings is 72 to 80
beats per minute.
14Deepa Unnikrishnan

15. Schematic diagram of circulation
15Deepa Unnikrishnan

16. Theheartisanorganpresentinourbodythatpumpsthebloodintheblood
vessels.
Itislocatedinthechestcavity.
Heartisroughlythesizeofyourfist.
Thehearthasfourchambers.
ThetwoupperchambersarecalledAtriaandtwolowerchambersarecalledventricles.
Thepartitionbetweenthechambershelptoavoidmixingupofbloodrichinoxygenwith
thebloodrichincarbondioxide.
16Deepa Unnikrishnan

17. Sections of human heart
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18. Heartbeat
Thewallsofthechambersoftheheartaremadeupofmuscles.These
musclescontractandrelaxrhythmically.Thisrhythmiccontraction
followedbyitsrelaxationconstituteaheartbeat.
ThestethoscopeisaninstrumentthatisusedtolistentotheHeartbeat
ofaperson.ItamplifiestheHeartbeatsothatthedoctorscanmonitorit
andfindoutthepatient'scondition.
18Deepa Unnikrishnan

19. Do all animals possess a circulatory system?
No,animalslikeHydraandSpongesdonotpossess
acirculatorysystem.
Theseanimalsliveinwaterandhencegetfoodand
oxygenfromthewaterasitenterstheirbodies.
Asthewatercomesoutoftheirbodies,ittakesaway
thecarbondioxideandwastematerialsoutofit.
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20. William Harvey
The English physician , William Harvey discovered the circulation of blood
20Deepa Unnikrishnan

21. EXCRETION IN ANIMALS
Thecellsinanimalsreleasesomewasteproductsasthey
performdifferentfunctions.
Thesewasteproductsaretoxicandhencetheymustbe
removedfromthebodiesofthelivingorganisms.
Theprocessofremovalofwasteproductsproducedinthe
cellsofthelivingorganismsiscalledExcretion.
21Deepa Unnikrishnan

22. EXCRETORY SYSTEM in Human Beings
The excretory system is an
organ system that helps in the
removal of waste material
formed inside the body .
The human excretory system
consist of
1. A pair of kidneys
2. A pair of ureters
3. A urinary bladder
4. A urethra
22Deepa Unnikrishnan

23. EXCRETORY SYSTEM
Kidneys–therearetwoorganscalledKidneyspresentinourbody.TheseKidneys
containbloodcapillariesthatfilterouttheunwantedsubstancesfromthebloodin
theformofurine.
Urinarybladder–TheurineproducedbytheKidneysisstoredinabladdercalled
urinarybladder.
Ureters–Therearetwotube-likestructureswhichconnecttheKidneysandthe
urinarybladdertogether.Theyallowpassageofurinefromthekidneytothe
bladder.
Urethra–Thereisamusculartubethroughwhichtheurinemovesoutofthebody.
23Deepa Unnikrishnan

24. Dialysis
sometimes a person's kidney may stop working
due to the infection or injury . as a result of
kidney failure , these products start
accumulating in the blood . such persons cannot
survive until their blood is filtered periodically
through an artificial kidney . this process is
called dialysis .
24Deepa Unnikrishnan

25. FACTS
An adult human being normally passes about 1-1.8 L of urine in
24 hours . The urine consist of 95% of water 2.5% of urea and
2.5% of other waste material .
The way in which waste chemicals are removed from the body of
the animal depends on the availability of water. Fishes and
aquatic animals excrete ammonia in the water.
Birds, Snakes and lizards excrete semi-solid, white coloureduric
acid.
25Deepa Unnikrishnan

26. FACTS
Howissweatusefultous?
Sweatcontainswaterandsomesaltsandhencehelpingettingrid
oftoxicwastesfromthebody.
Also,asthesweatevaporatesfromourskin,ittakesupourbody
heatandthismakesusfeelcool,especiallyduringthesummer
days.
26Deepa Unnikrishnan

27. Transportation in Plants
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Deepa Unnikrishnan

28. Transportation of Water and Minerals
Therootsoftheplantsabsorbtheessentialmineralsand
waterfromthesoil.
oTherootshavehairlikestructurespresentonthem.
oThesehairsincreasethesurfaceareaoftherootsand
henceallowmoreamountofabsorption.
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Deepa Unnikrishnan

29. Transportation of Water and Minerals
Fromtheroots,thewaterandmineralsaretransportedtootherpartsofthe
plantthroughspecialkindoftissuescalledvasculartissues.Therearetwo
vasculartissuespresentintheplants:
oXylem–Itisavasculartissuethatisresponsiblefortransportingnutrientsand
waterintheplants.Therootcellsabsorbwaterandmineralsandtransportitto
xylem.Xylemcarriesittootherpartsunidirectionallywithoutusageofenergy.
oPhloem–Itisavasculartissuethattransportsthefoodproducedbytheleaves
toallpartsoftheplant.
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Deepa Unnikrishnan

30. Transportation of Water and
Minerals
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Deepa Unnikrishnan

31. Transpiration
Sometimesnotallthewaterthatplantsabsorbisusedbythem.
Hence,theyneedtogetridoftheexcesswaterinthem.
Thislossofwaterinplantstakesplacethroughtheprocessof
transpirationinwhichthewaterevaporatesintheatmosphere
throughthestomatapresentontheleaves.
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Deepa Unnikrishnan

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Deepa Unnikrishnan

33. Importance of transpiration in plants
Transpirationresultsinabsorptionofwater:As
thewaterfromtheleavesevaporates,itgeneratesa
suctionpullintheplantsthatbringthewaterfrom
therootsupwards.
Transpirationhelpsincoolingdowntheplants:
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Deepa Unnikrishnan

34. Deepa Unnikrishnan
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