united nations association

The excretory system is represented by the kidneys, the ureters and the urinary bladder. Kidneys are composed of a large number of functional units called nephrons. Kidneys take up the function of excretion and osmoregulation. The excretory system is closely associated with the ..

Wild life resources include all animals, which grow and propagate naturally without any sort of human interference. They remain in wild form without any sort of friendly association with man. Invariably they are in forests. Wildlife serves as a resource to maintain the ecological balance ..

In hydrogen fluoride, hydrogen atom is bonded to highly electronegative atom, fluorine (electronegativity = 4). It has been found that in solid state hydrogen fluoride consists of long zig-zag chains of H-F molecules associated by H-bonds. On heating, progressively, the length of th..

Species is generally the lowest taxonomic rank representing organisms that are very much closely related to one another. A species is defined as a group of closely related, structurally and functionally similar organisms which can breed among themselves, producing fertile offspring and which are re..

The importance of maintaining the ecological balance and conservation of the resources has been increasingly becoming clear in the last two decades. It has now become necessary for all countries in the world to recognise this fact and plan what is known as 'sustainable development'. The Unite..

The branch of physics dealing with the study of optical phenomena is called optics. This can be divided into two categories, ray optics and wave optics. Wave optics describes the connection between waves and rays of light. The wave theory of light was put forth by Huygen and later modified by Frens..

Wave Optics - Introduction - The branch of physics dealing with the study of optical phenomena is called optics. This can be divided into two categories, ray optics and wave optics. Wave optics describes the connection between waves and rays of light. The wave theory of light was put forth by Huyge..

Era 1: Three Worlds Meet (Beginnings to 1620) Era 2: Colonization and Settlement (1585-1763) Era 3: Revolution and the New Nation (1754-1820s) Era 4: Expansion and Reform (1801-1861) Era 5: Civil War and Reconstruction (1850-1877) Era 6: The Development of the Industrial Unite..

Era 1: Three Worlds Meet (Beginnings to 1620) Era 2: Colonization and Settlement (1585-1763) Era 3: Revolution and the New Nation (1754-1820s) Era 4: Expansion and Reform (1801-1861) Era 5: Civil War and Reconstruction (1850-1877) Era 6: The Development of the Industrial Unite..

Era 1: Three Worlds Meet (Beginnings to 1620) Era 2: Colonization and Settlement (1585-1763) Era 3: Revolution and the New Nation (1754-1820s) Era 4: Expansion and Reform (1801-1861) Era 5: Civil War and Reconstruction (1850-1877) Era 6: The Development of the Industrial Unite..