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  • Biological diversity in the Himalayas Featured Article Biological diversity in the Himalayas Biological diversity in the Himalayas

    Stretching in an arc over 3,000 kilometers of northern Pakistan, Nepal, Bhutan and the northwestern and northeastern states of India, the Himalaya hotspot includes all of... More »

  • Limestone Featured Article Limestone Limestone

      Limestone  is a sedimentary rock whose chief mineral component is calcite (calcium carbonate: CaCO3). Limestone can be formed by precipitation of calcite... More »

  • Dugong Featured Article Dugong Dugong

    The Dugong, often referred to as the sea cow, is actually more closely related to elephants than to the bovine namesake.  Throughout much of their range, the Dugong has... More »

  • Carnivore Featured Article Carnivore Carnivore

    Introduction The term carnivore is used in a variety of ways. The general ecological definition of a carnivore is an organism that feeds on animals, as opposed to feeding... More »

  • Fluorine Featured Article Fluorine Fluorine

    Fluorine is a highly reactive chemical element with atomic symbol F. Having the atomic number nine, fluorine is the lightest halogen. Fluorine is a yellow-green gas... More »

  • Egypt Featured Article Egypt Egypt

    Egypt is a nation of eighty-four million people in north-Africa, it also controls the Sinai Peninsula, part of the Middle East and western-Asia. Thus, Egypt controls the only... More »

  • Gymnosperm Featured Article Gymnosperm Gymnosperm

    A gymnosperm is one of a number of non-flowering seed bearing vegetation species, including conifers, cycads, Ginkgo and Gnetales.  These species arose first in the... More »

  • Urushiol Featured Article Urushiol Urushiol

    Introduction Urushiol is an oily toxin produced by plants in the cashew family (anacardiaceae).  These plants include poison ivy, poison oak, and poison sumac, and... More »

Recently Updated
Europa Island Last Updated on 2016-01-13 02:13:53 Europa Island located in the southern Mozambique Channel, between Madagascar and Mozambique. Europa Island is about 100 kilometers (km) southeast of Bassas da India. Europa, with 30 square kilometers (km2) of land area, is 6-7 km in diameter with a maximum altitude of 6 meters (m). Its shallow lagoon (generally 1 m deep) is open to the sea at one side, and covers about 900 hectares (ha), including some 700 ha of mangrove swamp that is particularly extensive to the south. The lagoon is almost entirely exposed at low tide, and supports sparse seagrass beds at its outflow. These are dominated by Thalassodendron and Halodule species. Another smaller lagoon supports a mixed vegetation. The rim of the atoll is a karst is also a quantity of exposed coral rock and extensive sand dunes and rubble to the southwest. Europa is estimated to have formed about 90,000 years ago. It is... More »
Marine microbes Last Updated on 2016-01-01 20:01:01 Marine microbes is a term that encompasses all microscopic organisms generally found in saltwater. Most micro-organisms are acellular and fall into the major categories of viruses, prokaryotes (bacteria), and protists, groups which differ considerably in biological characteristics. While representatives of these groups are found in virtually everywhere in marine waters, and they play nearly every ecological role imaginable, their most important function is that they form the base of the food chain in marine ecosystems. Well-known to us as disease-causing agents, viruses are deceivingly simple organisms, little more than some nucleic acid within a protein container. They are 'parasitic particles' most about 40 nanometers in characteristic size. Viruses attach themselves to a living cell and inject a dose of nucleic acid into the cell; the injected nucleic acid... More »
India Last Updated on 2015-09-01 11:18:16 India is one of the major nations of the world. With 1,205 million people, it has the second largest population (after China). It is bordered by the Arabian Sea and Indian Ocean in the south, east and west. To the North, it borders Bangladesh, Bhutan, Myanmar (Burma), China, Nepal, and Pakistan. India has a long and complex history reflected in its intricate mixture of ethnic groups, languages and cultures. While, density populated, India is home to a wide range of varied ecoregions with important biodiversity.  Its major environmental issues include: deforestation; soil erosion; overgrazing; desertification; air pollution from industrial effluents and vehicle emissions; water pollution from raw sewage and runoff of agricultural pesticides and herbicides; tap water is not potable throughout the country; and, its huge and growing... More »
Nuclear power Last Updated on 2015-08-28 08:36:17 Nuclear power is the generation of electricity from controlled reactions within the nucleii of atoms that release energy used to boil water, the steam from which drives a turbine to generate electricity . All commercial nuclear plants presently rely upon nuclear fission reactions. As of 2010, approximately 14 percent of the world's electricity was derived from nuclear power, chiefly centered in the United States (with 31% of the world's total nuclear power capacity), France (16%), and Japan (10%). The International Atomic Energy Agency (IAEA) reports that, as of November 21, 2012, there are 437 nuclear power reactors in operation in 30 countries, plus Taiwan. Another 64 reactors under construction in 14 countries which if operational today would increase the worldwide electrical generation capacity of nuclear power by 17%. One hundred and forty reactors have been permanently... More »
Comoros Last Updated on 2015-07-18 16:21:28 Comoros is a nation of 730,000 people composed of three islands (Ngazidja or "Grande Comore", Mwali  or "Mohéli" and Nzwani or "Anjouan") in the Indian Ocean, at the northern mouth of the Mozambique Channel, about two-thirds of the way between northern Madagascar and northern Mozambique. Comoros also claims a fourth island Mayotte or "Mahoré" which is under French administration. One of the world's poorest countries, the islands comprising Comoros  have inadequate transportation links, a young and rapidly increasing population, and few natural resources. The country is not self-sufficient in food production. Rice, the main staple, accounts for the bulk of imports. The low educational level of the labor force contributes to a subsistence level of economic activity, high unemployment, and a... More »