WBPSC Prelims and Mains Notes-WBPSC Test Series
A molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass is called a polymer. A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Due to their broad range of properties,both synthetic and … Read more
Biodiversity and conservation Biodiversity, or biological diversity, is the variety of all life forms.Sum total of all the variety of living organisms on earth constitute biodiversity. There are three levels of biodiversity: genetic diversity—the variety of genetic information contained in individual plants, animals and micro-organisms species diversity—the variety of species ecosystem diversity—the … Read more
Atomic Structure In 1897 J.J. Thomson discovered electron as a constituent of atom. He determined that an electron had a negative charge and had very little mass as compared to that of the atom. Since an atom was found to be electrically neutral it was inferred that some source of positive charge must be present … Read more
Acid An acid is a substance which forms H+ ions as the only positive ion in aqueous solution. Examples:- Hydrochloric acid dissolved in water forms H+ and Cl– ions HCl —> H+ + Cl– Sulphuric acid dissolved in water forms H+ and SO42- ions H2SO4 —>2H+ + SO42- Nitric acid forms H+ and NO3– ions when dissolved in water HNO3 —> H+ + NO3– … Read more
The photoelectric effect The photoelectric effect is the emission, or ejection, of electrons from the surface of, generally, a metal in response to incident light.A material that can exhibit The photoelectric effect is said to be photoemissive, and the ejected electrons are called photoelectrons. The process was discovered by Heinrich Hertz in 1887. Attempts to … Read more
Respiratory System Introduction Red blood cells are like trucks that transport cargo on a highway system. Their cargo is oxygen, and the highways are blood vessels. Where do red blood cells pick up their cargo of oxygen? The answer is the lungs. The lungs are organs of the respiratory system. The respiratory system is the … Read more
Forestry in Rajasthan Rajasthan is blessed with great variety of natural resources ranging from scanty vegetation in the western arid region to mixed delicious and sub-tropical evergreen forests in the east and south east of Aravali ranges. Forest cover is 32744.49 sq.km.(12475 sq.km. is reserved, 18222 sq.km.is Protected Forest 2046.75 is unclassified forest) which is … Read more
Nuclear physics Atoms in nature generally are electrically neutral, as they have equal numbers of protons in the nucleus and orbiting electrons. However, within the nucleus there are other particles called neutrons, which are electrically neutral but have about the same mass as protons. There are two numbers used to characterize a nucleus: Z, the … Read more
India’s Missile program Introduction India’s missile programme took a shot from space programme, beginning 1967. In 1972, Rohini- a 560 two-stage, solid propulsion sounding rocket was developed and test fired India first launched its small 17-tonne SLV-3 space booster in 1979 India successfully injected the 35 kg Rohini I satellite into near-earth orbit in … Read more
WHO Defines Malnutrition as “Malnutrition refers to deficiencies, excesses, or imbalances in a person’s intake of energy and/or nutrients. The term malnutrition addresses 3 broad groups of conditions: undernutrition, which includes wasting (low weight-for-height), stunting (low height-for-age) and underweight (low weight-for-age); micronutrient-related malnutrition, which includes micronutrient deficiencies (a lack of important vitamins and minerals) or … Read more