...here are basically three categories of chemicals normally functioning in the body—elements, inorganic compounds, and organic compounds: {draw:frame} Elements are components of all chemical compounds. Of the 92 naturally occurring elements, only 20 are normally found in the body. Seven of these, carbon, oxygen, hydrogen, calcium, nitrogen, phosphorous, and sulfur make up approximately 99% of the human body weight. In most cases, the elements are components of inorganic or organic compounds. In a few cases, however, elements themselves may enter into chemical reactions in the body, e.g., oxygen during cell respiration, sodium in neurotransmission, and arsenic and lead in impaired mitochondrial metabolism. Inorganic compounds are important in the body and responsible for many simple functions. The major inorganic compounds are water (H2O), bimolecular oxygen (O2), carbon dioxide (CO2), and some acids, bases, and salts. The body is composed of 60-75% water. Oxygen is required by all cells for cellular metabolism and circulating blood must be well oxygenated for maintenance of life. Carbon dioxide is a waste product of cells and must be eliminated or a serious change in pH can occur, known as acidosis. A balance in acids, bases, and salts must be maintained to assure homeostasis of blood pH and electrolyte balance. Organic compounds are involved in nearly all biochemical activities involved in normal cellular metabolism and function. The mechanisms by which xenobiotics...
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...Biology 2F03: Lecture 1 Chapter 2: Life on Land • • • • • • • • Labs start on the Sept 17 Why horses and cattle help restore Guanacaste forest of Costa Rica? o This forest was in decline for thousands of years, when Indians colonized central America, it caused its decline. o Its regenerated when the Europeans came with the cattle o The trees only produce a new plant after processes: the fallen fruit has to be eaten by a larger animal (mule, or horse or cow) à it has to pass through the body and ends up in a pile of fertilizer only then it can regenerate and produce a tree o Why did it evolve to be depended to this process? § There must be animals there in the past, in the past it was a camel (llama, alpaca). When the Indians came from asia (50000 years ago) these animals went extinct and the tree lost its major dispersal system What is the most obvious foundation of life on land? o Is landà soil Climate defines biomes, the ‘shapes’ of vegetation o Defines the major types of land on earth o Temperature and precipitation to be specific Soils in turn greatly affect the aspects (roots, water, nutrient) à rentention, root attachment, etc. Soil typically form layers (horizontal) retaining a range of physical and chemical layers: o Classification of soil: O= organic, A, B, C Soil horizons: description o O: organic, litter on top, fine litter deeper (gets broken down, hence fine), pollen, dead organisms o A: mineral soil, some organic matter...
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...Question 1 Most insects use external sources of heat to achieve their operative temperature range. Heinrich's research on the sphinx moth (Manduca sexta) indicates that some insects can thermoregulate by using their flight muscles and: A. using their blood as a coolant. B. decreasing their metabolic rate. C. possessing an internal respiratory system. D. using a countercurrent heat exchange mechanism. Question 2 The thermal stability of aquatic environments is a result of the: A. high specific heat of water. B. low latent heat of vaporization of water. C. low latent heat of fusion of water. D. All of the choices are correct. Question 3 Animals that rely mainly on external sources of energy for regulating body temperature are called: A. epitherms. B. endotherms. C. ectotherms. D. peritherms. Question 4 In general, reptiles are considered to be a/an: A. poikilotherm. B. homeotherm. C. endotherm. D. heterotherm. Question 5 Mammalian and avian aquatic endotherms use all of the following mechanisms to thermoregulate EXCEPT: A. fat. B. internal respiratory systems. C. fur or feathers. D. concurrent heat exchange. Question 6 The water availability for organisms is determined by: A. internal dissolved ion concentrations. B. external dissolved ion concentrations. C. movement of water down its concentration gradient. D. movement of water...
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...Page No. 2 Index Swachh Bharat Mission FEB & MARCH, 2015 AUGUST, 2012 Page No. 4 Insurance Sector In India Page No. 5 Bharat Ratna Award Designed by: Chandan Kumar “Raja” For Advertisement Contact at : 9958790414 Join us at Facebook: https://www.facebook.com/iasexamportal Follow us at Twitter: https://twitter.com/iasexamportal CURRENT AFFAIRS National Issues International Issues India & the World Economy Science and Technology Sports Awards & Prizes In The News 6 14 20 23 39 51 58 64 Disclaimer: Editor and Publisher are not responsible for any view, data, figure etc. expressed in the articles by the author(s). Maps are notational . All Disputes are subject to the exclusive jurisdiction of competent courts and fourms in Delhi/New Delhi only. Selected Articles from Various Newspapers & Journals Page No. 67 91 Cyberspace Page No. 93 Regional Rural Banks The Mauryan Empire Model Paper G.S. Paper I 94 117 Join Online Coaching For IAS Pre & Mains Exams http://iasexamportal.com/civilservices/courses Project Mausam and Maritime Silk Route SWACHH BHARAT MISSION Throughout the world around 2.5 billion people do not have toilets to use, out of those 250 crore people 65 crore live in India alone. In order to solve this big challenge government of India has launched “Swachh Bharat Mission” on the birth anniversary of Mahatma Gandhi and former Prime Minister Lal Bahadur Shastri...
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