81. According to US water standards, the maximum permissible coliform count (number/100 ml) in recreational waters is A. 10, 000 B. 5,000 C. 1,000 D. 500 Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
82. A simple and relatively inexpensive film-flow type of aerobic treatment method is A. Septic tank B. Activated sludge process C. Percolating filter system D. All of the above Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
83. Which one is exhaustible but renewable natural source? A. Fossil B. Petroleum product C. Forest D. Coal Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
84. General circulation model (GCM's) are used to A. Predict climate B. Predict cyclones C. Study ocean currents D. Study temperature on wind Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
85. At the present time volcanoes are confined to certain limited areas of the Earth's surface. This special zone is called A. Trans - Atlantic volcanic zone B. Circum - Pacific Ring of fire C. Central - Pacific Inter - Continental zone D. Indian - Ocean volcanic belt Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
86. A small reduction in ozone concentration can lead to a large increase in the amount of harmful ultraviolet radiations reaching the earth in the wavelength region of A. 200 - 205 nm B. 220 - 225 nm C. 260 - 265 nm D. 295 - 300 nm Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
87. A synthetic chemical compound that is not naturally available in nature is A. Probiotics B. Xenobiotic C. Epibiotic D. Antibiotic Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
88. Which one of the following is a valid assumption regarding the molecular clock hypothesis in evolution? A. For a given protein sequence, mutations accumulate at a constant rate in all lineages B. For a given protein sequence, mutation rates are different in different lineages C. All proteins evolve at the same constant rate D. For a given linage, mutation rates are the same for all proteins Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
89. The orchid seeds do not germinate under ordinary conditions because A. Orchid seeds are too large for disposal B. Orchid seeds do not have endosperm C. Orchid seeds undergo a dormancy period D. They germinate under very dry conditions Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
90. Genes for biodegradation of xenobiotics by Pseudomonas are located on A. Plasmids B. Genome C. Trascriptome D. Proteome Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
