CGPSC MAINS 2017 Paper-4

Points to Remember: Habitat: Diverse topography, including rainforests, grasslands, and shorelines. Major Species: High levels of endemism (species found nowhere else), including plants, amphibians, reptiles, birds, and mammals. Environmental Importance: Biodiversity hotspot, crucial for water security, climate regulation, and carbon sequestration. Conservation Status: Declared a UNESCO World Heritage Site, but faces threats from deforestation, habitat … Read more

Points to Remember: Preparation of oxygen gas in the laboratory. Diagrammatic representation of the apparatus. Three physical properties of oxygen. Three uses of oxygen. Introduction: Oxygen (O₂) is a vital element, essential for respiration in most living organisms and crucial for numerous industrial processes. While oxygen constitutes approximately 21% of the Earth’s atmosphere, obtaining pure … Read more

Points to Remember: Primary alcohols oxidize to aldehydes and then carboxylic acids. Secondary alcohols oxidize to ketones. Tertiary alcohols do not oxidize easily under normal conditions. Oxidation reactions involve the loss of electrons or an increase in oxidation state. Introduction: Alcohols are organic compounds containing a hydroxyl (-OH) group attached to a carbon atom. They … Read more

Points to Remember: Photophosphorylation: The process of ATP synthesis using light energy in photosynthesis. Cyclic Photophosphorylation: Involves only Photosystem I (PSI), producing ATP but not NADPH. Non-cyclic Photophosphorylation: Involves both Photosystem II (PSII) and PSI, producing both ATP and NADPH. Electron flow: Understanding the path of electrons through the photosystems and electron transport chain is … Read more

Points to Remember: Non-renewable energy sources are finite and deplete over time. Their extraction and use often have significant environmental consequences. They are currently the dominant energy source globally, but their use is increasingly challenged by concerns about sustainability. Different non-renewable sources have varying environmental impacts and extraction challenges. Introduction: Non-renewable energy refers to energy … Read more

Points to Remember: Madhya Pradesh and Chhattisgarh’s bio-resource reserves. Geographical area (in km²) of each reserve. Description of each reserve’s significance. Introduction: Bio-resource reserves are protected areas designated to conserve biodiversity, including flora, fauna, and genetic resources. They play a crucial role in maintaining ecological balance and supporting sustainable development. Madhya Pradesh and Chhattisgarh, states … Read more

Points to Remember: IUCN Red List Categories reflect the extinction risk of species. “Critically Endangered” signifies an extremely high risk of extinction. “Vulnerable” indicates a high risk of extinction in the medium-term. The criteria for each category are quantitative and based on population size, decline rate, geographic range, and other factors. Introduction: The International Union … Read more

Points to Remember: Primary, secondary, and tertiary alcohols differ in the number of carbon atoms attached to the carbon bearing the hydroxyl (-OH) group. Lucas reagent is a solution of anhydrous zinc chloride in concentrated hydrochloric acid used to distinguish between primary, secondary, and tertiary alcohols based on their reactivity. IUPAC nomenclature follows systematic rules … Read more

Points to Remember: Definition and basic principle of a transformer. Distinction between step-up and step-down transformers. Formula for transformer efficiency and its components. Introduction: A transformer is a passive electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. It does this without changing the frequency of the current. Transformers are … Read more

Points to Remember: Cathode rays are streams of electrons. They are negatively charged particles. Their properties were crucial in the discovery of the electron. Understanding cathode rays is fundamental to understanding atomic structure and modern electronics. Introduction: Cathode rays are streams of electrons emitted from the cathode (negative electrode) of a vacuum tube when a … Read more