Water pollution 

70 of our planet is covered with water. However only about 3 of earth water is fresh. Fresh water is needed by humans ans plant  so we should control the pollution of water.  Addition of pollution into water bodies such as rivers or lakes is called water pollution.  Bathing animals  washing cloths and utensils in water bodies also lead to pollution. Immersion of idols during festivals. Chemical wastes bodies. If harms and kills aquatic flora and fauna. Pollution water caues diseases like typhoid diarrhoea cholera jaundice.

As water is a bad conduct of heat so there is alway an uneven heating pattern noticed in case of land mass and mass and water bodies. In summer the landmass of northern Indian is much hotter that the surrounding water in the oceans most of the times. The air above the land becomes hot up and rise and the wind from the ocean carrying water bodies these winds called winter monsoon bring scanty rainfall to coastal tamil Nadu  as they take moisture while blowing over Bay of Bengal.

Differant types of storms are caused by strond by strong air cirrents and are accompanied by lightning heavy rains and high speed winds lightning there the storms may occur on land or over the seas.                             Thunderstorm.               Thunderstorm occur in hot humid tropical areas such as india most frequently. the air over the land gets heated becomes light  and rises. In doing so the water vapour condenses fast form tiny droplets of Water which freeze forming ice particles during the condensation of water  vapour and freezing of droplets. A large a large anount of heat is given out which further pushes the air up at a  higher speed.

Mosquitoes and malaria

Mosquitoes do not live in water, but, they lay eggs in stagnant water for example in ponds water collected in types bucket uncovered tanks, drains, water coolers, etc. when a mosquito lays an egg the egg changes into larva that floats in water within a few mosquito is born feale .mosquitoes need to such animals blood for their eggs to develop properly. Mosquitoes arry the germs of dangerous diseases such as dengue and malaria which if not treated on time. Can even kill people. A person suffering from malaria has high fever along with shivering a person suffering from dengue has fever, vomiting joint pains rashes and body ache. It is important to prevent the outbreak of dengue and malaria by following some easy steps .

A large variety of animals flourish in water. They are called aquatic animals.fish is the most common aquatic animal and can be found in any water body like lake, river, sea, etc. a variety of fish lourish in water. Some of the common species of fish are cod, tuna, salmon, bass, etc. many types of fish are a source of food for man. Shark is a powerful and dangerous aquatic fish. It has powerful sense of hearing and can detect it's prey several miles away. It is known for its powerful sharp teeth. 

      Mammals

Whale is the biggest animal on earth. It is found in the open season. It look like. A fish but actually it is not a fish. It is a mammal and it's body is more than 23 metres long. It is even larger than the largest dinosaur. It weighs more than 150 metric tons. It has a blowhole on top of its head from where it breathes and makes fountain of water when it comes close of the surface. Dolphin is another common aquatic animal.

Plants growing in water are called aquatic plant. It you look at the plants growing in a pond you will find the some plants keep floating on surface of water while some other plants have roots inside the water and their leaves come up to the surface of water. Some other plants remain completely below the surface of water. Aquatic plants are of the following three types:       1. Floating plants 

Plants that floating on water are called floating plants. These plants are small in size. They have spongy stems or air - filled parts that help them to float freely. Such plants are mostly found in ponds and lakes where the water temins stagnant these plants protect small water animals from the hot sun buckweed, water lettuce and water hyacinth are a few free - floating plants.

2. Fixed plants.

Some plants are fixed to the ground below the water. Plants of lost and water lily have this kinde  of bodies. Long, porous stems link the fixed roots of the leaves that keep floating on surface of the water. The leaves of these plants evaporate huge amount of water as they have many stomata on their upper side. The hollow stem of lotus is eaten as a delicious vegetable while it's flowers are well - known for their beauty. 

3. Submerged plants.

Plants that hrow under water are called submerged plants. These plants are fixed to the water bed. Hydrilla ballisneria and tape grass are some examples.

              Pollution 

Any activity carried out  put by human beings which harms the environment is known pollution. The substrate or gases which cause pollution are called pollutants. 

   Typer of pollution 

    1* Air pollution.

     2* water pollution 

     3* Noise pollution.            4* soil pollution.

Natural and humans cause air pollution. Nature pollution the air by sandstorms forest fires eruption of volcanoes and pollens from flowers. However most air pollution is caused by human activities. Burning of fuels is factories and vehicles burning of garbage, release of smoke and harmful gases into the atmosphere are the activities that cause air pollution.

Health care 

Health care does not only mene availability of doctors and doctors and hospital for treatment and cure of diseases but also established ways and means to prevent diseases and to make people healthy and strong.                                       Community heslth

India is a highly populated country and it is a major task for the government to tackle health problems. Moreover, due to lack of literacy, many people believe in many myths and superstition which come in the way of science treatment. Both central and the state governments are responsible for the health of the people. The health care agencies that are responsible for taking care of the community health include. 

*1. Various departments of the ministry of health and family welfare. 

*2. Private and non- government organisation

 National health Programmes are set up to tackle the threat of communicable and non - communicable diseases. These programmes. Promote the threat of communicable and non - communicable diseases. There programmes promote general health and well being of the people. the ministry frames the policies and plans for these programmes. There are programmes like anti - malaria or the national T.B. control programme. NGO's also adopt health Programmes to reduce incidence of diseases like AIDS and leprosy provide health care facilities and aslo educate people about various health issues.some villàges do not have health care centres. The people have to travel to far away cities and towns for medical aid which is a great discomfort to the patient and his family it also costs a lot of money. In some remote areas our government has launched mobile bispensaries whereobile vans visit on fixed days. 

A situation which poses immediate threat to our life and property is called an emergency. Wars and natural disasters may lead to an emergency buring such times, many people become homeless and lose their means of livelihood. They require immediatel help in terms in terms of food clothing medicines and shelter.   An act of nature which results in loss of life and property is called a natural disasters. Earthquake cyclones tsunamis and floods are some common natural disasters. The major types of disasters are explained below. When surface of  the earth trembles it is called an earthquake we can feel shocks of an earthquake. The shocks many be mild or severe. When a strong. Buildings can develop completely collapse. Many people are.injured and many of them die. Rescue teams try to reach quickly to the spot and start their rescue operations. They bring out the injured people from the debris and rush them to the hospital.

Any material the is burnt to generate energy is called a fuel  give energy for vehicles to move. The process by which fuel is couverted into energy is called combustion. Typer of fuel fuels can be divided into two groups. 1. Fossil fuels.   2. Alternate fuels.                  Fossil fuels are obtained from the remained of dead plants and animals that were deep in the earth millions of years ago . Fossil fuels exhaust easily and take a long time to form again coal petroleum and natural gas are fossil fuels. 

Mountain experions 

Mountain experions make mountaineers physically and mentally strong. It helps to build leadership qualities. It also makes one disciplined and sincere. Mountain expedition also teaches a person to remain calm in different situation. Once the mounyaineers scale a peak, they hoist their national flage to show respect to their countrry. Many men and women have risked their lives to climb the himalyan peaks. Sherpa Tenzing  Norgay and sir edmund hillary were the first to climb mouth everest. They did so in 1953. Mountaineer training  the are many instituons that train people for the difficult mountain climbing the Nehru institute of mountaineering and himalyan mountaineering instite are two important places where people get training to become professional mountaineers. In some schools and adventure camps children are trained for mountaineering on artificial rocky surfaces. The base camp also serves are centre of operation for climbers. It  has normally houses fix machines laptos and other communcation equipment. Doctors are available at the camp.the rough are tough bachendri pal was the first Indian woman and the fifth climbing in the world to climb mount Everest in 1984. She was born at nakuri in garhwal. At the age of 12 she started  mountain climbing with her friends.