11 12 13 14 Height of a plant is regulated by: a) DNA which is directly influenced by growth hormone. b) Genes which regulate the proteins directly. Growth hormones under the influence of the enzymes coded by a gene. d) Growth hormones directly under the influence a gene. A sportsman, after a long break of his routine exercise, suffered muscular cramps during a heavy exercise session. This happened due to: a) lack of carbon dioxide and formation of pyruvate. b) presence of oxygen and formation of ethanol. c) lack of oxygen and formation of lactic acid. d) lack of oxygen and formation of carbon dioxide. An object is placed in front of a convex mirror. Its image is formed : a) at a distance equal to the object distance in front of the mirror. b) at twice the distance of the object in front of the mirror. c) half the distance of the object in front of the mirror. d) behind the mirror and it's position varies according to the object distance. When light enters the atmosphere it strikes on extremely fine particles, which deflect the rays of light in all possible directions, This is due to - a) reflection of light b) atmospheric refraction c) scattering of light d) dispersion of light