Science Master

A. Hydrochloric acid B. Lactic acid C. Uric acid D. Methanoic acid Solution: A Hydrochloric acid is found in the human stomach. Its chemical formula is HCl, and it helps in digestion by decomposing complex, large food molecules into simpler ones. The acid activates the pepsinogen enzyme, which is necessary for protein digestion. It also kills dangerous germs in the stomach. Hence, (a) is the correct answer. Know more about Vitamins and Minerals and their deficiency diseases .

  A. NaAlO 2 B. H 2 O C. Al 2 O 3 D. SiO 2      Solution: D The Chemical formula for Silica is SiO2. Silica is the common name for Silicon Dioxide. It is commonly found in quartz. SiO2 forms 3-dimensional network solids in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms.  Hence, option (D) is correct. Read more about Chemical Compounds and their formulae .

A. Femur  B. Malleus  C. Stapes  D. None of the above  Solution: C  Stapes bone present in the ear is the smallest bone in human body. Femur is the longest bone in human body. Hence, option (c) is correct. 

A. Liver B. Pancreas  C. Thyroid D. Hypothalamus Solution: A Liver is the largest gland of human body. Liver is a spongy mass of wedge-shaped lobes that has many metabolic and secretory functions. It is located on the right side of the abdomen. Hence, option (A) is correct.  Watch explanation of this question here . 

A. Precipitation B. Condensation C. Transpiration D.  Evaporation Solution: A Rain, hail, and snow are the three most common types of precipitation. Rain: Rain is a type of precipitation that occurs when water droplets fall to the surface of the Earth. When rain falls from the clouds, but freezes before it reaches the ground, it is referred to as ice pellets or sleet. Hail: Hail forms in the clouds of a cold storm. It forms when droplets of very cold-water freeze, or turn solid, as soon as they touch things like dust or dirt. Snow: Snow is the type of precipitation that falls in the form of ice crystals. The ice crystals are formed individually in clouds, but when they fall, they stick together in clusters of snowflakes. Hence, (A) is the correct answer. Read Geography Study Material important for the preparation for NDA 2023 exam. Visit UPSC website for updates regarding NDA exam.

A. seeds   B. roots C. fruits D. flowers Solution: B Pneumatophores are specialized root structures that grow out from the water surface and facilitate the aeration necessary for root respiration in hydrophytic trees.  Such hydrophytic trees are mangrove species, bald cypresses, and cotton gum. Hence, option (B) is correct.