THE GREENHOUSE EFFECT.

A natural regulation system there is a basic relationship between the photo synthesis of green plants and the respiration of living beings. This relation ship not only maintains forest life but it also preserves the biosphere.

SOIL

Soil is made up of broken bits of rock , minerals plants and animals. It covers most soil ground in the world. It takes thousands of years for bigger pieces of rock minerals and rotted plants and animals to from the small particles that make up the soil.

Fossil

            Fossil one formed from the remains of dead animals or plants. Looking at fossil tells us about animals and plants that lived a long time ago.

Forest

A forest is an area where a lot of trees grow close of all the land on the earth . The amount of forest goes down every year.

Food chain

               All animals need to eat to get energy. Some animals eat other animals. Some animals eat energy passes from one creature to another.

Comet

                  A comet is giant ball of ice , gases and rock. It looks like a star with a glowing tail. Comets can only be seen as they get close to the sun

EARTH

The Earth is our planet. IT is one of nine planets that move through space around the sun. The Earths takes one year to travel once around the sun. It is just the right distance from the sun to be worm enough for people , animals and plants to live on but not so not that all water dries up.

Distance aroun the                                                                                                                                                           

The equator ……………………   40,075  Km

 

Distance from the 

Surface to the centure…………....   6,300  Km

Temperature in the

Earth’s core…………………….    4300 C

Distance of the Earth

From the sun……………………   149.5 million Km

 

 ANIMALS

Aardvark.

An aardvark is an insect-eating mammal which lives in African  . Its name means ' earth pig ' in the dutch language . 

   Aardvark facts.

  Of kinds - 1

  Color    - beige-grey

  Length   - 1.5-1.9 m

  Height   - about 50 cm

  Status   - common 

  Life spar- 10 years 

  Enemies  - dogs , pythons , lions , leopards , warthogs.

Alligator.

The alligator is a very big reptile that lives in rivers , lakes and swamps . It is a close relative of the crocodile . On type live in south-east USA , while  the other lives in south -east Chaina . The alligators snout is less pointed than the crocodiles and the teeth are different .

  
                Alligator facts 

           Of kinds  - 2

           Color     - greyish-brown

           Length    - up to 4 m

           Weight    - up to 250 kg

           Status    - threatened 

           Life span - up to 60 years 

Bat

Bat are the only mammals that can fly . Most bats fly at night . they avoid crashing into things by making high noises that bounce off objects to give echoes . The echoes help bats to find their ways of the world except the arctic and Antarctica .

                                                                                          Bat facts.

Of kinds  - more than 2000
Color     - black , brown , grey or yellow .
Wingspan  - usually 20-30 cm .
Weight    - usually 5-40 g .
Status    - common .
Life span - 15-25 years . 
Enemies   - cats , owls , fores , skunks , snakes .

Bear

Bears are very strong and powerful mammals . Bears live over most of the northern hemisphere . The biggest bear. the smallest is the sun bear.

       Bear facts .

   Of kinds  - 7
   Color     - black  , brown  , red , bluish , white  or cream 
   Length    - 1.3-3 m
   Wingspan  - 90 cm to 1.5 m
   Weight    - 50-65 kg
   Status    - some are threatened 
   Life span - 25 years
   Enemies   - people hunt bears for their fur.

Tiger 

Tigers are mammals . They are the longest and strongest members in Asia.

      Tiger facts

  Of kinds  - 8
  Color     - golden , orange , with black stripes 
  Length    - up to 3 m
  Weight    - up to 270 kg
  Status    - endangered 
  Life span - 15-40 or years
  Enemies   - peoples 








Owl

The owl is a bird of prey which hunts of night. there are many different kinds of owl that live all over the world.

   Owl facts.

Of kinds  - 133
Color     - usually brown or brown and white 
Length    - up to 72 cm
Weight    - up to 800 g
Status    - common 
Life span - up to 18 years 
Enemies   - eagles , buzzards , peoples

Ant

An ant is a small insect. it lives with other ants in a group called a colony. Some colonies have just a few ants but other colonies have thousand of ants. Ants live in all but the coldest parts of the earth.

     Tiger facts

  Of kinds - over 10,000
  Color     - black , brown or red
  Length    - 0.1-2.5 cm 
  Status    - common 
  Life span - from a few weeks to 20 years
  Enemies - anteaters , birds , frogs , lizards , spiders , other insects , peoples 

river fish

the movement of fish.

in order to better service in the water , fish respond to different stimuli . the response to light ,for example , is very important for fish . some respond negatively , that is , they avoid light and remain at the bottom of the river . the fish called miller's-thumb lays it's eggs beneath rocks and submerged tree trunks and the males watch over them until the eggs are hatched.

 SRI LANKA RIVER FISH

ACID RAIN

acid substances.

Some substance , such as lemon juice or vinegar , have  a characteristic acidic taste . the pH scale is an indicator used to determine the degree of acidity of a substance . On the pH scale distilled water is neutral with a reading of 5 .

When rain water has a degree of acidity lower than 5 , it is acid ; this means that is contains some dissolved acid substance , generally sulphuric and and nitric acid such acids from gases produced by power stations , industries and motor vehicles.

contaminating acids.

Once they are formed , sulphuric and nitric acid return to the earth's surface through rain , fog and snow , or simply by bonding to solid particles that fall to the ground.

acid rain transmits its acidity to rivers , oceans and lakes , to villages and cities , to fields and forests such acidity impoverishes the nutritional capacity of the soil as it alters the population of microorganisms . Forests and subjected to the effects of acidity as well , be cause the rain and low clouds in acid particles.