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Impact of Climate Change on Biodiversity

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  Climate change is due to the green house effect, the process by which absorption and emission of infrared radiation by gases in the atmosphere warm the earth’s lower atmosphere and surface. Atmospheric gases such as water vapour, CO 2 , O 3 and CH 4   act like the glass roof of a greenhouse trapping heat which results in the warming of the planet. That is why it is seen to be analogous to that which occurs within green houses. Man’s actions such as the burning of fossil fuels, farming activities and land use changes have all resulted in an increase in these natural gasses. The earth’s surfaces and lower atmosphere are thus warming rapidly. The phenomenon of ‘Global Warming’ was discovered by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896. The physical aspects of global warming, i.e. how and why it occurs and the climate models that are used to predict future changes in the global climate will be dealt with in detail in the nex...

Cyanobacreria

 

Importance of microorganisms in everyday life

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  The maintenance of life on earth depends on the continued recycling of inorganic materials and the decomposition of organic matter. Microorganisms play an important role in these processes. For many elements microorganisms are the only biological agents capable of regenerating key forms of the elements needed by other organisms, particularly by plants. Crop production has increased with the improvement in agricultural practices. Some examples of such practices are cultivation of free-living, nitrogen-fixing, cyanobacteria for increasing rice production in paddy fields, use of nitrogen-fixing microorganisms to inoculate legumes and use of microorganisms to break down waste material and crop debris for re-use by new crop plants. Microorganisms have long been used to produce animal feeds and human food. Examples in this category are single-celled proteins (SCP) (e.g., algae such as Spirulina , Scenedesmus and Chlorella ) used as animal feed; mushrooms and yeasts used for huma...

What is microbiology?

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  Microbiology is a scientific discipline dealing with the study of organisms which cannot be seen with the naked eye and can therefore only be seen with the   aid of a microscope.   This is because human eye cannot resolve any object smaller than 1/10 mm in diameter. Most microscopic organisms are only a few thousandths of a millimetre in size and are collectively referred to as microorganisms. Main groups of organisms generally studied under microbiology are bacteria, fungi, viruses, algae and protozoa. Birth of microbiology Although Robert Hooke describes the fruiting structures of fungi in 1660 the first person to see microorganisms in any detail was Anton van Leeuwenhoek  (1632-1723). He was not a trained scientist but a merchant whose interest was to grind lenses and construct microscopes. The instruments he made were not more powerful than magnifying glasses capable of enlarging objects up to 200 to 300 times. One complete original Leeuwenhoek’s microscope i...

Terpenoids

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Terpenoids are a class of organic compounds, which are widespread in nature. The mixtures of substances that contain the fragrant compounds of plants are called “essential oils,’’ and the majority of terpenoids occur in the essential oils of many plants and flowers, and some in gums and resins. A few terpenoids have been isolated from animal sources also. They contain the “essence” or the odour of the plant. Practically, you are familiar with distinctly pleasant odours (aromas) produced by many plants. The fragrances of pine and cedar trees, flowers (e.g. rose, jasmine, etc.) peppermint, turpentine, cinnamon, cloves, and camphor (moth balls) are just a few of the examples one can name. All these aromas, of course, are the result of the volatile compounds produced by the plants. Many of them are valuable, because of their use as flavourings, perfumes, spices, incense, medicines, and insect repellents. Classification of terpenoids Number of isoprene units Number of carbo...

Water for Sustainable World

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Water resources are sources of water that are useful of potentially useful to humans. Uses of water include agricultural, industrial, household, recreational & environmental activities. Virtually all of these human uses require freshwater. 97% of water on the earth is salt water. Remaining 3% exists as fresh water of which slightly over two third is frozen in glaciers and polar ice caps. Unfrozen fresh water is mainly found as groundwater, with only a small fraction present above ground (surface water etc.) or as atmospheric water vapor. Freshwater is a renewable resource, yet the world’s supply of clean, fresh water is steadily decreasing. Water demand already exceeds supply in many parts of the world purely because the world population continues to rise, so too does the water demand. In this context it is important to use water in a wise way =   sustainable use Sustainable use of water The use of   water that   supports the ability of human society to endu...