How Does Pollination Take Place

Pollination means transferring of pollen from the anthers of a flower to the stigmas of a flower. Pollination is necessary for fertilization, for the formation of seeds. Pollination takes place in a number of ways, it can be done by insects, animal or small birds. It can also be done by the blowing wind or flowing water. Most flowers are adapted by nature to pollinate using the above methods. It is easy to find flowers which are pollinated by insects because they are brightly colored for attracting insects. Besides this many flowers have in them a sweet nectar which is consumed by insects like bees. Such flowers have both the male and female reproductive parts within them.

When an insect enters them the pollen on the anthers sticks to the body parts of the insect and as it moves inside the flower the pollen gets transported to the female reproductive organs. Wind movement also helps the pollen drop off from the anthers into the carpels. When insects or the wind transport the pollen from one flower into the copies of another flower, it is known as cross pollination.

Another form of pollination is self pollinating. This takes place when the pollen is transferred one  flower to another flower on the same plant, or from one part of a flower to another part of the same flower.
Pollination By Animals: Certain flowers are designed in such a way that the chances for cross pollination by insects increases. For example, the petals join together and deliberately form a tube. The nectar is at the base of the tube. Insects have to crawl right into the base of the tube to suck the nectar. As a result of this there are greater chances of there brushing against the anthers and stigmas. Flowers that are pollinated by insects are shaped differently. They have special petals which act like a landing pad. Honey guides or special lines on the petals guide the insects into the flower. The size and the shape the insect which may enter and pollinate the flower. This increases the chance of pollination.

No pollen is wasted and it is transported by the insects to various varieties of flowers. Bees and butterflies play an important role in pollinating flowers. They have hairy bodies, ideal for picking up pollen grains. Buttercups are plants having simple flowers shaped in such a way that they are open and almost any creature entering they can complete the job of pollination.

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Life Cycle Of A Plant

Sexual reproduction depends upon flowers. The male portions are the stamens and the female sex organs are known as stigma, which will receive pollen and ovary, in which the ova or the embryo seed grows. Wind or insects, like bees or flies, carry grains of pollen to the stigma.

Then the grain of pollen grows a pollen tube, which penetrates the ovule. The nucleus of both the pollen grain and the ovule cell fuse to produce an embryo. After the embryo grows, a food store known as the carpel is formed, along withe the endosperm and the testa or seed coat. When the seed ripens, the fruit is formed after the stamens, petals and sepals, all fall off. Either the wind or an animal carries the fruit away. If there are suitable conditions of warmth and moisture, germination of the seed occurs. First a tiny root grows. Next comes a leafy shoot. The young baby plant gets its food from the cotyledons. They also have the job of protecting the first time leaves. Enclosing the stamens and carpels are the petals, which are often brightly colored, pear nectar-producing organ and are supported by the sepals.

The cross section of the leaf, below, shows that the leaves bear cells rich in chloroplasts and are the major food producing organs. Gas flow in and out of leaf spaces through holes, the stomata, in the underside. Water enters the leaf via conducting vessels leading up from the roots. Food produced in the leaf travels around the plant via sieve tubes. Leaf veins comprise vessels, tubes and strengthening cells. The stem support the leaves and flowers, and conducts food and water between the leaves and roots. Like the leaves, it is covered in an epidermis layer that gives protection from damage and infection by bacteria, fungi and viruses, and prevents water loss. In trees, the stem is woody and covered in a protective bark.

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How to Water vapour and Rain

All living things need water to exist. If there was no rain there would not be any drinking water. All the water, which is needed on earth, is provided by rain. All plants, including grass, crops and trees need water to live. Though the atmosphere there is a constant movement of water. Water vapor, which is invisible, rises into the air and falls to the earth as rain. .Evaporation of water: The steam, which you saw from water boiling in a kettle, can be very dangerous. Serious burns can result from the heat energy contained in the steam and in the boiling water. Using a source of heat, water can be boiled. This heat energy causes atoms to break away from each other after a liquid reaches its boiling point. The atom, then evaporates. Energy from the hot sun's rays on molecules of water can cause them to break away from the water surface and evaporation takes place. As molecules evaporate, they carry away the heat energy. However, during  the process of evaporation, the liquid temperature remains constant. Boiling often takes place naturally near active volcanoes when they erupt. Condensation: The turning of water vapor into water is called condensation. This process occurs when water is converted from its gaseous state back into the liquid state.

When water molecules lose their heat energy they condense. This process of condensation is exactly opposite to the process of evaporation. Heat or dry air causes evaporation. Cold air causes condensation. If water vapor toss a cold surface or an object, it condenses. Water is turned into invisible water vapor by the heat of the sun's rays. The process of rain begins with the evaporation of tiny particles or molecules of water from the rivers, lakes, the seas and the oceans. The hot rays of the sun cause the water molecules to evaporate. When they evaporate they are lifted from the water surfaces into the air. Then the rise with the wind in cooler air. The turning of water vapor into water is called condensation. In cooler air, tiny drops of water vapor condense around dust particles. When they float about as masses of minute water droplets, at considerable heights above sea level, they form clouds. When the droplets in clouds coalesce into larger drops between 0.2mm and 6mm they fall as rain. Rain, which falls on the ground, finds its way back to the seas.
The water that falls as rain comes mainly from the oceans and the seas. Before the water becomes rain, it passes through two stages: evaporation and condensation

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Environment Pollution-Effects-and How to Prevent

The things which makes the world most worried is environment pollution. our environment comprise the elements the surround us. Air, water, the sun, the moon, weather, climate and everything fall under the category of environment. Environment makes us survive. We get everything from nature to meet the need of our life. But this environment is polluted and makes us too much worried. Increasing pollution of our environment turns the world into an abode of destruction. Today our environment is polluted and pollution exerts damaging influence on our existence.

How to become polluted
How air gets polluted: The world is producing millions of tons of domestic rubbish and toxic industrial waste each year, and it is becoming increasingly difficult to find suitable locations to get rid of all the refuse. The disposal of various kinds of waste is seriously polluting the environment. We know that air is an important element of our environment  and our air is polluted by smoke. Man makes fire to cook food, make bricks, melt tar for road construction and to do many other things.

Fires create smoke and pollute the air. Railway engines and powerhouses create smoke by burning coal and oil. Mills and factories also belch a lot of smoke. Buses, trucks and cars use petrol and diesel oil. These too emit smoke. All these kinds of smoke pollute the air.

How water gets polluted: Water, another vital element of the environment, is also polluted in different ways. Man pollutes water by throwing waste into it. Farmers use chemical fertilizer and insecticides in their field. When rain and floods wash away some of these chemicals, they get mixed with water in rivers, canals and ponds. Mills and factories also throw their poisonous chemicals and waste products into rivers and canals and thus pollute the water.

Water vehicles also pollute rivers by dumping oil, food waste and human waste into them. Insanitary latrines and unsafe drains standing on river and canal banks are also responsible for further pollution. Thus water is contaminated by various kinds of waste and filth.

How sound gets polluted: Sound pollution is another hindrance to a calm and serene life. There are so many disturbing sounds made by man and machine. Making loud sounds without caring for human disturbance is a cognizable offense. When motor vehicles pass way whistling loudly, people may be faced with health hazards.

Even using loud speakers indiscriminately disturbs our sleep and peaceful life. People suffering from hypertension or heart diseases may have heart attack or stroke if they hear loud sounds. Loud sound may affect the mental upbringing of a baby.

Problem caused by environmental pollution
Viewing the present pollution around the world it seems that there lies a universal conflict between nature and man. Nature is used for serving the purpose of man. Again it is antagonistic to man. Nature is, at times, wild and destructive to humans. Once man was indifferent to his need, he was not moved with easy life and  comfort. But in course of time, population increases and scientific inventions also get increased and man is compelled to think of the environment. To make life comfortable, to make pleasure and recreations man begins to manufacture various chemicals and materials that harm the flow of the environment. Pollution starts in water- land- space. Researchers find that causes of cancer and deformity of human child are the effects of devastating use of chemicals. On the other hand, Greenhouse effect is a recent concept which means the adverse effects caused by the rise in the temperature in the climate of the world. The excess of gas, smoke and other particles emitted by the industries, auto-engines and other places is being accumulated at a height in the space. This gaseous accumulation has created an obstacle for the heat caused by the sun on the earth to be spread in the space. As a result the heat comes back to heat the water on the surface and the climate. This situation is called greenhouse effect in scientific terminology in modern times. The snow in the poles will gradually melt and the water level of the sea will rise. This is no doubt a terrific possibility for the world. Excess of industrialization is on of the main causes of green house effect. Indiscriminate deforestation throughout the world also is one of the causes to create imbalance in the climate and it, in turn, helps Greenhouse effect to intensify. We also know that, our world are becoming warm day by day.

Over industrialization is the main causes of global warming. Global warming is heightened by the rapid growth of industry, the use of chlorofluorocarbon in packaging and manufacturing commercial products, the use of detergents such as washing powder and washing-up liquid and so on. However, the main culprits for global warming are carbon dioxide gas, produced by the burning of fossil fuels and forests and pollutants such as methane and chlorofluorocarbon.

How to be prevent

The whole world is worried about the preventive ways for tackling environmental pollution. In different countries laws are passed to stop environment pollution. Recently " strict ban on the use poly bags"  is declared and legal operations in these respect are going on. This step is very helpful for preventing environment. Every pollution is harmful for us. So, I think consciousness is only one things for preventing environment. Some steps are very effective to prevent environment pollution.
1. Don't melt tire.
2. Don't use polythene.
2. Manage waste.
3. Don't use wood or coal for burnings bricks.
4. Safely use insecticides and fertilizer.
5. Don't make smoke.
6. Use whistle, if need.

Environment is the basis of our existence. To ensure our existence we should remain free from all sorts of pollution. Actually population problem is the stumbling block in the way of tackling the increasing pollution. Future prospect of our world is under darkness because we cannot find out pragmatic solution of our environmental crisis. The common people should be brought to the fact that environment pollution must be stopped any how. Proper education is crying need for the backward class. All of us should remember the importance of the slogan,"Save the environment, ensure the healthier life".

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