51. Which of the following has the least wavelength? A. X-rays B. Microwaves C. Ultra Violet rays D.Radio waves 52. Ozone layer of atmosphere absorbs A. Visible radiations B. Infrared radiations C. Ultraviolet radiations D. Radio waves 53. ARadio active element "X" with a half life of 2 hours decay giving a stable element "Y". After a time of t hours the ratio of atoms is 1 : 7 then, the value of A. 4 hours B. 6 hours C. 5 hours D. 14 hours 54. The root nodules of Casuarina which are capable of symbiotic nitrogen fixation contain the microbe A. Rhizobium B. Frankia C. Anabaena D. Azotobacter 55. Which cytoplasmic organelle is associated with 'acrosome' formation in the spermatozoa of animals? A. Lysosome B.Chloroplast C. Golgi complex D. Chromosome 56. Deficiency of folic acid leads to A. Anaemia B. Mental disorder C. Scurvy D. Night blindness 57. Which of the following is a social insect? A.mosquito B. locust C. bedbug D.termites 58. Which one. of the following is NOT correctly matched? List I List II Hormone Secreted by I. Testosterone - Interstitial cells II. Prolactin - Adrenal medulla III. Estrogen - Ovary IV. Progesterone - Corpus luteum A. I only B.II only C. III and II D. IV only 59. Point out the correct statement in the following: A. Indus people Worshiped Lord Indra B. Indus civilization was a rural civilization C. Iron was unknown to the Indus people D. The 'Great bath' was located at Harappa 60. Name the social reformer who supported Dr. Muthulakshmi Reddy for the abolition of Devadasi system. A. E.V. Ramasamy Naicker B. T.M. Nair C. C.N. Anna Durai D. Natesa Mudaliar
