Quick review of important concepts asked in the UPSC exams.
India has monsoon type of climate. The word 'monsoon' refers to the seasonal reversal of the wind direction in a year. Due to this, India has four prominent seasons - cold weather season, hot weather season, advancing southwest monsoon season and post or retreating monsoon season.
The diversity of plants and animal provide us food, fuel, medicine, shelter and other essentials without which we cannot live. Bio-diversity is a short form of biological diversity. In simple terms, bio-diversity is the total number of genes, species and ecosystems of a region. It includes (i) genetic diversity (ii) species diversity and (iii) eco-system diversity.
The Constitution of India has made alternate provision for the structure and functioning of all the three branches of the government - executive, legislature and judiciary, The President, the Council of Ministers with Prime Minister constitute the executive branch of the Government, the Parliament with its two houses - House of the People or Lok Sabha and Council of States or Rajya Sabha is the legislative branch and the Supreme Court heads the judicial branch.
In an ecosystem, living organisms interact among themselves and also with the surroundings. Ecosystem is divided into two basic categories - terrestrial and aquatic. Humans can also make ecosystems. For example, aquarium, gardens and agricultural fields are examples of man-made ecosystem.
India is said to be the land of farmers and these farmers are mostly living in the rural India. Various types of agricultural activities are found in different parts of the country. Agriculture is categorised into different types on the basis of purpose of farming.
Elements are broadly classified as metals non-metals. Metals can be distinguished from non-metal on the basis of their physical properties like malleability ductility, lusture. Metals have tendency to lose electrons whereas non-metal have tendency to gain electrons. Thus, metals show electropositive character whereas non-metals show electronegative character.
Water is essential for survival of all living beings. Although sea water is the largest natural source of water, it is unfit for domestic use and drinking. Decantation, filtration, chlorination and boiling are some of the steps that convert non potable water into potable water.
Cell is the structural and functional unit of life. A typical cell includes a cell membrane, cytoplasm and genetic material either within the nucleus or in the cytoplasm. The cytoplasm contains cell organelles such as mitochondria, endoplasmic reticulum lysosomes, vacuoles, ribosomes, golgi bodies.
Acids are the substances which taste sour, change blue litmus red, are corrosive to metals and furnish H+ ions in their aqueous solutions. Bases are the substances which taste bitter, change red litmus blue, feel slippery and furnish OH– ions in their aqueous solutions.
The basic cause of chemical bonding is to attain noble gas configuration either by transfer of electron from a metal to non-metal or by sharing of electrons between two non-metal atoms. All the atoms have a tendency to acquire stable state or noble gas configuration and is called Octet Rule.
A chemical equation is a shorthand description of a reaction. It symbolically represents the reactants, products and their physical states. In a balanced chemical equation, number of atoms of each type involved in the chemical reaction is equal on the reactants and products sides of the equation.
Measurement is a process of comparing a physical quantity with a standard quantity. The standard quantity used to compare a physical quantity for its measurement is called unit. The internationally accepted modern system of units used in science is known as SI units.
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