The main elements that determine the climate of a place are:
- Distance from the sea
- Altitude or height above sea level
- Humidity
2. What are th e th re e ty p e s of a d a p ta tio n s th a t a n im a ls d e v e lo p to su rv iv e in d iffe re n t c lim a te s?
2. WEATHER
The weather of a place can be defined as the
measure of its daily atmospheric conditions such
as humidity, temperature, lightning events,
rainfall Storms, snow and so on.
Different elements of weather are:
Rainfall
Tem perature
Humidity
Snowfall
Storms
Winds etc.
3. A w eat her r ep or t gener al l y c ont ai ns t he i n or m at i on
abou t t he w eat her o t he d ay.
T he gover nm ent has a sp ec i al d ep ar t m ent c al l ed t he
M et eor ol ogi c al Dep ar t m ent t hat p r ed i c t t he w eat her
o a p l ac e and p r ep ar e t he w eat her r ep or t .
T he w eat her r ep or t i s gener al l y p u bl i shed i n
n e w s p a p e r s , r a d i o and television.
T h e w e a t h e r o r e c a s t is i m p o r t a n t o r people
bec
w e a t h e r conditions. For Example, w e can check the
p
an u m b r e l l a w i t h us a c c o r d i n g l y.
Weather
Forecast
4. T he w eat her o a p l ac e i s never c onst ant . I t c an al t er ever y d ay or
even e v e r y hour. For instance, the w e a t h e r m i g h t be sunny in the
m o r n i n g in an a r e a b u t r e a l l y in the evening.
T he w eat her r ep or t o a p l ac e al w ay s i nc l u d es t he m i ni m u m and
m a x i m u m t e m p e r a t u r e s o the d a y w h i c h a r e m e a s u r e d using a
m i
exp er i enc ed i n t he m or ni ng t i m e w hi l e t he m axi m u m t em p er at u r e i s
experienced in the a ternoon.
T o m e a s u r e the r a i n a l l o a p l a c e an i n s t r u m e n t c a l l e d the Rain
Gauge is used. T h e r a i n gauge c o l l e c t s the r a i n w a t e r o o r i g i n and
has a m e a s u r i n g s c a l e w h i c h d e t e r m i n e s the q u a n t i t y o r a i n a l l o
t h a t p l a c e .
5. Anychangein theweatherofaplaceontheearthis becauseofthe Sun
whichradiateslargeamountsofheatandlight energyonthe earth. The
formation ofwinds, thephenomenaofrainfall andthe changein
seasons,all occurbecauseoftheSun.
Whydaysareshorter in thewinter season?
Weknowthat theEarthspinsonanaxis aroundthe sun.
Hence,theamountofsunlight aplacereceivesvarious throughout the
yearasits positionwith respecttothesunchangesbecauseof the
rotation oftheEarth.
Thisalsoleadstochangein theseasonsofaplace.
Inthesummerseason,thepositionoftheplaceis closertothesun and
henceit receivessunlight for longerhourswhilein thewinter season
thepositionofaplaceis farther tothesunandhence,it receives
sunlight for shorterhours.
How do
changes in
weather occur?
6. Climate
The climate of a place can be
defined as the prevailing weather
conditions of the place for a long
period of time, for example, 25
years.
For Example, the temperature of
Rajasthan is generally high
throughout the year and it does not
receive much rainfall so we can say
that Rajasthan is a hot and dry
place.
7. Climate and Adaptation
The climate of a place can affect the
living organisms of that area.The
animals living in a particular region
adapt themselves so that they can
survive the weather conditions of that
place.The features and habits of the
animals start to change as per the
climate of the place.
8. A d a p t a t i o n s are of three types:
( i ) S t r u c t u r a l a d a p t a t i o n s A d a p t a t i o n of special body p a r t s of an
o r g a n i s m t h a t helps i t to s u r v i v e i n i t s n a t u r a l h a b i t a t , e.g. s k i n c olour,
shape, body covering.
( i i ) B e h a v i o u r a l a d a p t a t i o n s A d a p t a t i o n of special w a y s i n a p a r t i c u l a r
o r g a n i s m t h a t helps i t to s u r v i v e i n i t s n a t u r a l h a b i t a t . I t u s u a l l y occurs i n
response to some e x t e r n a l s t i m u l i , e.g. f r o g s and bear undergoes
h i b e r n a t i o n o r w i n t e r sleep d u r i n g h a r d w i n t e r season.
(iii) Physiological a d a p t a t i o n s A d a p t a t i o n of body s y s tems pres ents i n an
o r g a n i s m t h a t a l l o w s i t to p e r f o r m the c e r t a i n bioc hemic al reaction, e.g.
w a r m - b l o o d e d a n i m a l s are able to keep the c o n s t a n t body t e m p e r a t u r e .
A n i m a l s t h a t live i n a v ery cold o r h o t c l i m a t e m u s t possess special
features to p r o t e c t themselves a g a i n s t extreme cold o r heat. The features
and h a b i t s t h a t help an a n i m a l to adapt to t h e i r s u r r o u n d i n g are a r e s u l t
of the process of evolution. According to t h e i r h a b i t a t a n i m a l s adapt
themselves. These a n i m a l s m a y be grouped as p o l a r r e g i o n and t r o p i c a l
r a i n f o r e s t a n i m a l s .
9. Thenorthern region of Himalayas has coldandmoderately wetclimate
(e.g. Kashmir).
Plains has amoderately hotandwetclimate (e.g. Uttar Pradesh).
South has very hotandwetclimate (e.g. Kerala).
Thewesternregion has hotanddry climate (e.g. Rajasthan).
North-Eastern India has wetclimate (e.g. Assam) andreceives rain for a
major part of the year.
C l i m a t e s i n I n d i a
Theclimate of India varies indifferent regions. These canbedescribed as
below:
10. The several factors that determine the climate at a place
are
Distance from the sea Climate of a place varies according to
the closeness of the sea. The places that are near the sea,
are moderate (not too hot nor too cold), e.g. Mumbai,
Chennai. While the places that are away from the sea have
extreme climate, having very hot summer or too cold
winter, e.g. Delhi.
Altitude or height above sea level Climate also varies
according to the altitude. The higher altitudes are cooler,
e.g. Himalaya.
Humidity It also determines the climate of a place. Kolkata
and Kerala have high humidity, while. Rajasthan and
Haryana have low humidity.
FFACTORSTHATDETERMIINETHE
CLLIIMATE
11. T h e a re a of t h e e a r t h t h at s u r r o u n d s t h e N o r t h Po l e a n d
t h e S o u t h Po l e is c a l l e d t h e Po l a r Re g i o n .
T h e c l i m a t e of t h e polar r e g i o n is e x t r e m e l y c o l d
t h r o u g h o u t t h e ye a r a n d r e c e i v e s h e a v y s n o w.
T h e s u n d o e s n o t rise for 6 m o n t h s of t h e ye a r in t h e
polar r e g i o n a n d t h e n It s t ay s u p for t h e n e x t 6 m o n t h s .
T h e t e m p e ra t u r e in t h e polar r e g i o n c a n b e a s l o w a s -
37°C.
Most c o m m o n a n i m a l s f o u n d in t h e s e r e g i o n s are polar
b e a r s a n d p e n g u i n s . O t h e r a n i m a l s t h at c a n b e f o u n d in
polar a re a s are fishes, birds, oxen, m u s k , reindeers, fox,
w h a l e s a n d seals.
T h e y h a v e a d a p t e d t h e m s e l v e s s o t h at t h e y c a n s u r v i ve
easily in t h e s e p l a c e s .
POLAR REGION
12. ThePolar BearThe white fur of the polar bear makes it easier for them to hide in the snow
and therefore save them from predators.
In the same way, it makes it easier for them to catch their prey.
The polar bears have two layers of thick fur on them so t hat they can survive
extremely cold conditions.
The polar bears move slowly and rest a l o t so t hat they do not get overheated
because of their thick fur.
The polar bears often swim on warm days to keep themselves cool.
The paws of the polar bear are large and wide so t hat it can swim as well as walk
easily in the snow.
The polar bear can swim underwater as well because it can keep its nostrils closed
for a long time.
The strong sense of smell of polar bears makes it possible to locate its prey during
such harsh weathers.
13.
14. Penguins
The penguins are also white in colour so that they
can hide in the snow.They have thick skin with large
fat content in their body so that they can survive the
cold weather easily.The Penguins generally live in a
crowd or nest closely so that they can stay
warm.The Penguins have webbed feet which allow
them to swim
15. M i g r a t o r y B i r d s in the Polar Region
T h e birds in o r d e r to protect themselves r o m cold weather o the w i n t e r s in the p o l a r
region o ten m i g r a t e r o m these areas to w a r m e r places.
T h e y then r e t u r n back a t e r the w i n t e r season.For example, T h e Siberian crane migrates
to I n d i a in Rajasthan, Haryana and some North East regions during the w i n t e r season in
Siberia.
T hese bi r ds t hat m i gr at e t o di er ent pl aces du r i ng a change i n w eat her ar e o t en
c a l l e d m i g r a t o r y birds.
T h e y can t r a v e l used instances o 15000 k m to protect themselves r o m the extremely
cold environment.Such birds m i g r a t e to the same places every year.
T h e m i g r a t o r y birds l y very high so that the heat generated by the l i g h t wings can be
disposed o in the cold conditions.
T h e m i g r a t o r y birds have a sense o direction so that they can t r a v e l to the same place
every time.
T h e m i g r a t o r y birds also use l a n d m ar k s o r o l l o w the direction o the sun and s t a r s to
migrate.Some birds also use the magnetic i e l d o the earth and ind direction
. A p a r t r o m birds, ishes, insects and m a m m a l s also migrate.
16. TROPICALRAINFORESTSThe tropical regions on the earth are the regions wh i c h are close to the
equator and hence receive m o r e a m o u n t of sunlight during the year.
Because of this, these areas have a h o t climate.
The temperature in tropical regions can be as high as 40o C and can
d r o p until 15 o C only.
The length of the day and n i g h t are almost equal in these regions.
However, there is a lot of rainfall and so the tropical rainforests are
f o u n d in this region.
The Tropical rainforests are h o m e to a wi d e variety of vegetation and
animals.
Due to large habitation, th e animals often c o m p e t e for food in
these regions.
Many animals have a d a p t e d themselves so that they can live on the
trees and find their food easily. The skin colour of these animals is
generally similar to that of the surroundings so that they can catch their
prey easily and protect themselves f r o m the predators. Also, m a n y of
these animals have a g o o d eyesight and better sense of hearing.
17.
18.
19. Adaptations in Elephant
Elephant is a well-known animal of Indian tropical rainforest. These are plant eaters and are adapted
in many remarkable ways to survive in tropical rainforest. These adaptations can be discussed as
follows:
(i)The elephant has a long trunk which is used as nose and has a strong sense of smell. It also helps
elephant to pick up the food. The long trunk is also used for breathing. It can reach up to the branches
of trees and help it to eat tree leaves. It is used for sucking water from lakes or rivers (drinking).
(ii) The elephant possesses tusks (long pointed teeth) that are used in tearing the bark of trees which
the
elephant loves to eat as food. It also helps elephant to fight their enemies and protecting themselves.
(iii) The elephant has large ears that help it to hear even very soft sounds and can sense the danger. It
also helps the elephant to keep it cool in the hot and humid climate of the tropical forest.
(iv) The feet of the elephant is large and round which help it to provide good stability and also prevent
it from sinking into soft ground due to its heavy weight.
20. Adaptations for hot climates
Deserts are h o t by day, cold at night, a n d receive very little rainfall.
The c a me l
Camels are well a d a p t e d for survival in th e desert. Their adaptations include:
large, flat feet - to spread their w e i g h t on th e sand
thick fur on th e t o p of th e b o d y for shade, a n d t h i n fur elsewhere to allow easy
heat loss
a large surface area to v o lu me ratio - to maximise heat loss
th e ability to go for a long t i m e w i t h o u t water - they lose very little water t h r o u g h
urination a n d perspiration
th e ability to tolerate b o d y temperatures u p to 42°C
slit-like nostrils a n d t w o rows of eyelashes - to h e lp keep o u t sand
21. 1 . N a m e th e e l e m e n t s that d e te r m i n e th e w e at h e r of a place.
Ans. The temperature, humidity, rainfall, wind-speed, etc. are called the elements that determine the weather of a place.
2 . W h e n are th e m a x i m u m a n d m i n i m u m te m p e rat u re likely to o c c u r d u r i n g th e d ay ?
Ans.The maximum temperature of the day occurs generally in the afternoon and the minimum temperature occurs in the early
morning.
3. Fill in th e b l a n k s
( i ) T h e a v e ra g e w e at h e r t a ke n over a l o n g t i m e is called __________
( i i ) A p l a c e receives very little rainfall a n d th e te m p e rat u re is h i g h t h r o u g h o u t th e year, th e c l i m ate of that p l a c e will b e
________ a n d _________
( i i i ) T h e t wo re g i o n s of th e earth with ex t r e m e c l i m at i c co n d i t i o n s are __________ a n d ____________
Ans. climate of the place (ii) hot, dry (iii) polar, tropical regions
n c e r t e x e r c i s e
22. Q.4.Indicate the type of c l i m ate of the following areas:
(a) Jammu and Kashmir:
(b) Kerala:,
(c) Rajasthan:
(d) North-east India:
Ans.(a) Jammu and Kashmir—moderately hot and moderately wet climate.
(b) Kerala—very hot and wet climate.
(c) Rajasthan—hot and dry climate.
(d) North-east India—The north eastern India receives rain for a major part of the year, hence wet climate.
Q.5.Which of the t wo c h a n g e s frequently, we at h e r or c l i m ate ?
Ans.Weather
23. Q.6.Followings are s o m e of the c h arac te r i sti c s of animals:
(i) Diets heavy on fruits , (ii) White fur (iii) Need to migrate (iv) Loud voice
(v) Sticky pads on feet (vi) Layer of fat under skin
(vii) Wide and large paws (viii) Bright colours
(ix) Strong tails (x) Long and large beak
For each characteristic indicate whether it is adaptation for tropical rainforests or polar regions. Do you think that some of these
characteristics can be adapted for both regions?
24. 7 . T h e tropical rainforests h a s a l arge p o p u l ati o n of animals. E x p l a i n w h y it is so.
Ans. Because of continuous warmth and rain, the tropical region supports an enormous number and a wide variety of animals
8 . E x p l a i n wi th exa m p l e s , w h y w e find a n i m a l s of certain k i n d living in particular c l i m ati c conditions.
Ans. Animals are adapted to survive in the conditions in which they live. Features and habits which help them to adapt to their
surroundings are the result of evolution. So, to survive in a particular type of climate the animals must have certain adapted
features. This is the reason we find animals of certain kind living in particular climatic conditions. For example, animals in the polar
region are adapted to the extremely cold climate. They have special characteristics, such as white fur, strong sense of smell, a layer
of fat under the skin, wide and large paws for swimming and walking in snow etc
Q.9. H o w d o e l e p h a nt s living in the tropical rainforests a d a p t t h e m s e l v e s ?
Ans. The elephant has adapted to the conditions of rainforest in many remarkable ways. It has a trunk that it uses as a nose
because of this it has a strong sense of smell. The trunk is also used by it for picking up food. Its tusks are modified teeth. These
can tear the bark of trees that an elephant loves to eat. So, the elephant is able to handle the competition for food very well.
Large ears of the elephant help it to hear even very soft sounds. They also help the elephant to keep cool in the hot* humid
climate of the rainforest.
25. Q.10.Choose the c o r re c t opti on w h i c h a n s w e r s the fo l l o w i n g question:
A car n i vore w i t h stripes o n its b o d y m o v e s ver y fast wh i l e c a t c h i n g its prey. It is likely to b e fo u n d in:
(i) polar r e g i o n s (ii) d e s e r t s
(iii) o c e a n s (iv) tropical rainforests
Ans. (iv) tropical rainforests
Q.11.Which fe atu re s a d a p t polar b e a rs to live in ex t r e m e l y c o l d c l i m ate ?
(i) A white fur, fat below skin, keen sense of smell.
(ii) Thin skin, large eyes, a white fur.
(iii) A long tail, strong claws, white large paws.
(iv)White body, paws for swimming, gills for respiration.
Ans.(iv) A white fur, fat below skin, keen sense of smell.
Q.12.Which opti on b e st d e s c r i b e s a tropical r e g i o n ?
(i) hot and humid
(ii) moderate temperature, heavy rainfall (iii) cold and humid (iv) hot and dry
Ans.(i) Hot and humid