What is the Food Chain?

    The "Food Chain" is defined as the sequence of energy transfer from Organism to Organism in the form of food. The Chain begins with green plants when they make their own food from water, chemicals in the soil and air, and sunlight. Plants are the primary food source. There are many food chains in eco-system. In a simple food chain, a herbivorous (Plant-eating) animals eaten by a larger Carnivorous (flesh eating) animals. Each of the links in the chain is called a trophic level. The chains do not normally extend beyond four or five atrophic levels. A common example of a simple food chain is the grass-cow-human chain. An example of ocean food chain is; Plankton-Snail-Small fish-Large Fish-Shark. In a parasite chain, a smaller organism consumers a part of a larger host, and may itself be parasitized by even smaller organisms.

    Every living things has its place in one or more food chains Though plants make their own food, animals cannot do so and depends on others (Plants or Animals) for their food. Since most of the chains are interconnected, they are called a Food Web. There are some animals that feed and survive only on one kind of food. If that one source is eliminated, the concerned animals will die. This will break the food chain and it may cause many environmental problems. 

    In a food chain, energy is lost in the form of heat at each step or Trophic level. Therefore by-passing one step would add to the energy gains. In the over-populated areas, people commonly increase the total food supply by cutting out a step in the food chain. Instead of eating goats that eat plants, they themselves eat plants. as the food chain is made available to the final consumers is increased.

Do you know how was Coal Formed?

     Coal is a fuel which is found in layers under the Ground. These layers are called Coal Mine’s from where coal is obtained. Coal is known as Fossil Fuel because it was made million years ago from dead plants. Coal is used for heating and is making Electricity, Gas and Chemicals. It is also made into another fuel called Coke. It is the most abundant fossil fuel in the world and it meets 30% of the world’s energy demands.

    Formation of Coal began 250 million years ago in an age called Carboniferous Period. During that period our earth had many swamp like seas. Because of Hot, moist climate gigantic plants were not able to grow. When the plants died, they sank into the swamp and new plants replaced them. As the newer plants died, layers of dead materials began to form. Mud and sand settled on top of this layer and pressed some of the water out. Eventually the land rose and more plants grow on the surface. These new plants died, decayed and were covered by the sediments again. This cycle continued for millions of years. Many layers of Stratified matter formed as decaying material were forced further beneath the surface. Great pressure was produced by these many layers. The pressure together with the chemical reactions gradually transformed the decayed material into coal. In this way coal was formed in many layers inside the earth. Today we have to dig to great depth to obtain it.

    Coal consists mainly of carbon, hydrogen, oxygen and nitrogen. There are four types of coal: Peat, Lignite, Bituminous and Anthracite. Peat is a material in the first stage of coal formation. It contains 90% of water. Dry Peat contains 60% Carbon. Lignite contains 60-75% carbon. Bituminous contains up to 80% Carbon. Anthracite is the final product of the coal formation, which contains 95% carbon.

    The leading coal producing countries are the USA, Soviet Union, China, Germany, Poland and Great Britain. In India Coal mines exists in Andra Pradesh, Bihar, West Bengal, Rajasthan, Maharashtra, Orissa, Assam, Jammu & Kashmir and Madhya Pradesh. About three billion tonnes of coal is mined every year in the whole world. India accounts for about 100 million tonnes.

 

What is Cholesterol?

Cholesterol is an organic compound belongs to the steroid group, which occurs in a free state or as esters of fatty acid in all animal tissues. In a normal man it is about 0.3% of his average weight. It is the starting material from which the body produces bile acid, steroid hormones and pro-vitamins in the body. It is used by the body to help digestion as well.

Cholesterol was discovered in 1812. Its name arise from its occurrence in Gallstones derived from the Greek Word "Chole-Stereos-al" meaning Bile Solid. The Formation of Cholesterol occurs in various tissues and organs particularly the Brain, Liver and Arteries.

The Increase in its quantity beyond a certain level can be harmful to our body. Excess of cholesterol gets deposited in the wall of Arteries will cause blockage and hardness, which affects the free-flow of Blood. Due to this, quantity of blood flow decreases and consequently the oxygen supply will also get decreased. This condition is termed as Arteriosclerosis. 

We know that Coronary Arteries play a vital role for the Heart to function. They provide oxygen and carry blood to the heart. If this get blocked the particular part of the heart may stop functioning, which leads to Heart- Attack.

Cholesterol can be controlled by a Balanced Diet. A high concentration of Cholesterol is present in the foods of Animal Origin like Meat, Egg, Butter etc... Doctors commonly advices to avoid such foods by substituting foods like Fruits, Vegetables, Cereals and so on.

Lowering Cholesterol level in blood reduces the risk of Heart-Attack. Many other measures can also be taken to maintain the Cholesterol level by giving up Smoking, regular exercises, avoiding Over-eating and avoiding fatty Substances.