Q1. Himalayan rivers are perennial because (a) They flow from inexhaustible springs in the Himalayas (b) They are fed in summer by melting snow of Himalayas (c) There is continuous rain throughout the year in the catchment areas (d) None of the above (UPSC Prelims 1981) Answer: (b) They are fed in summer by melting …
Q1. Why the Indian farmers plough their fields during the time interval between two crops ? (a) In order to keep the soil loose for further cultivation (b) To increase the porosity of the soil (c) To escape drought (d) To prevent clodding (UPSC Prelims 1981) Answer: (d) To prevent clodding Explanation: Ploughing between crops …
Q1. Colour blindness is (a) More common among women (b) Very rare in women (c) Very rare in men (d) Found to the same extent in both the sexes (UPSC Prelims 1981) Answer: (b) Very rare in women Explanation: Colour blindness is a sex-linked genetic disorder, typically carried on the X chromosome. Since males have …
Q1. Why camphor disappears when kept on a plate? (a) It sublimes (b) It reacts with the metal of the container (c) It reacts with the gases of the air (d) None of the above (UPSC Prelims 1981) Answer: (a) It sublimes Explanation: Camphor undergoes sublimation, meaning it changes directly from a solid to a …
Q1. The sex of the offspring is determined, when (a) The conception takes place (b) The sperm fertilises the ovum (c) The embryo is partially developed (d) The end of gestation period is near (UPSC Prelims 1981) Answer: (a) The conception takes place Explanation: The sex of the offspring is determined at the moment of …
Q1. Which organ is associated with the production of insulin in the human body? (a) Pancreas (b) Liver (c) Kidney (d) Heart Answer: (a) Pancreas Explanation: The pancreas produces insulin, a hormone that regulates blood sugar levels. Specifically, insulin is secreted by the beta cells in the Islets of Langerhans within the pancreas.
Q1. A person with which blood group will be a universal donor? (a) A (b) B (c) O (d) AB (UPSC Prelims 1981) Answer: (c) O Explanation: People with blood group O are considered universal donors because their red blood cells do not carry A or B antigens, making them compatible with all other blood …
Q1. Which of the following is commonly present in the acids? (a) Oxygen (b) Hydrogen (c) Sulphur (d) Nitrogen (UPSC Prelims 1981) Answer: (b) Hydrogen Explanation: All acids contain hydrogen ions (H⁺), which are responsible for their acidic properties. When dissolved in water, acids release hydrogen ions, making hydrogen the defining element in acidic compounds. …
Q1. Which of the following statements is true? (a) Both salinity and density of sea increase with depth (b) Both salinity and density of sea decrease with depth (c) Salinity increases but density of sea decreases with depth (d) Salinity decreases but density of sea increases with depth (UPSC Prelims 1981) Answer: (a) Both salinity …
Q1. How the body temperature is maintained ? (a) Due to temperature regulating mechanism located in the base of the brain (b) Due to excessive intake of water (c) Due to regular intake of foods (d) Due to the constant flow of blood in the capillaries (UPSC Prelims 1981) Answer: (a) Due to temperature regulating …