Notes and Study material for Exams
Allotropes of carbon Allotropy is the property of some chemical Elements to exist in two or more different forms, or allotropes, when found in nature. There are several allotropes of carbon. Diamond Diamond is probably the most well known carbon allotrope. The carbon atoms are arranged in a lattice, which is a variation … Read more
Diseases of Plants caused by Fungi Early Blight of Potato The disease is quite common in India, and occurs on about three week old plants. Since this blight occurs earlier than the ‘late blight’ of potato (caused by Phytophthora infestans), it is called ‘early blight.’ Prevention Measures: Field sanitation and rotation of … Read more
Diseases of Plants caused by bacteria Aster yellows Aster yellows,caused by a phytoplasma bacterium, affecting over 300 species of herbaceous broad-leafed plants. Aster yellows is found over much of the world wherever air temperatures do not persist much above 32 °C (90 °F). As its name implies, members of the family Asteraceae are … Read more
Diseases of Plants caused by viruses and their prevention Some of the same types of viruses that infect humans can also infect plants. Plants and humans do not transmit viruses to each other, but humans can spread plant viruses through physical contact. Most frequently, plants catch a cold when an insect or other … Read more
Digital divide & its prevention Digital technologies have spread rapidly in much of the world. Digital dividends—the broader development benefits from using these technologies have lagged behind. In many instances digital technologies have boosted Growth, expanded opportunities, and improved service delivery. Yet their aggregate impact has fallen short and is unevenly distributed. For … Read more
Digestive System Introduction The respiratory and circulatory systems work together to provide cells with the Oxygen they need for cellular Respiration. Cells also need glucose for cellular respiration. Glucose is a simple sugar that comes from the food we eat. To get glucose from food, digestion must occur. This process is carried out … Read more
Determinants of Nuclear Tests: Pokhran I (1974) and Pokhran II (1998) Pokhran 1 test The emergence of China as fifth nuclear power in October 1964 constituted a significant threat to India’s territorial Integrity and Sovereignty. The strained relations between the two countries after the 1962 aggression sparked off an acrimonious debate on defence … Read more
Defluoridation and other Techniques of water purification Defluoridation Defluoridation is the downward adjustment of the level of fluoride in drinking water. Worldwide, fluoride is one of the most abundant anions present in groundwater. Fluoride is more present in groundwater than surface water mainly due to the leaching of Minerals. Groundwater accounts for 98 … Read more
Concept of pressure Pressure is the perpendicular force per unit area, or the Stress at a point within a confined fluid. The pressure exerted on a floor by a 42-pound box the bottom of which has an area of 84 square inches is equal to the force divided by the area over which … Read more
Concept of Biotechnology The term ‘Biotechnology’ may Sound futuristic, but it is nearly as old as civilization itself. We have begun growing crops and raising animals 10,000 years ago to provide a stable supply of food and clothing. We have been using the biological processes of Microorganisms for 6,000 years to make useful … Read more