15 topics about sociology Essay Example | Topics and Well Written Essays - 3000 words

15 topics about sociology - Essay Example At present, a majority of the world’s population has or is living in a city; and yet, it was only about 100 years ago when there were only about 12 cities in existence. This speaks much of the pace and speed by which urbanization has taken place in various towns and rural areas. The growth in the population in these cities has also exceeded expected numbers for regular cities. These cities are called megacities because the rate of population growth and of development has increased and risen to unprecedented levels. And â€Å"we now live in an urban world where the mega-metropolises: Tokyo-Yokohama and greater Mexico City have populations of over 20 million† (Palen, p. 2). The rapidity of change from rural to urban life is at least as important as the amount of urbanization because the success or failure of the transition from rural to urban life is very much dependent on the pace of the development and the reception of the people to the development. And the megacities now cater to more advancement in industry and technology. The pace of these advancements is fast and is manifesting on a massive scale. But a large proportion of the world’s population is still based in the rural areas and in most Western nations. And the pace of transition from rural to urban life has been a dramatic transition as most population growths have been seen in the cities. Much of the population growth and transitions from rural to urban areas have been exhibited in developing countries. And these third world nations have managed to experience an expansion of their cities because many of the citizens seek greener pastures in these cities. As a result, today, â€Å"th e number of people living in developing world cities outnumbers the entire population of the world only 100 years ago† (Palen, p. 3). These numbers indicate that the pace of transition from rural to urban life has as much impact and importance as the amount of

Microbiology Bioremediation Essay Example | Topics and Well Written Essays - 750 words

Microbiology Bioremediation - Essay Example [1] There are a number of cost/efficiency advantages to bioremediation, which can be employed in areas that are inaccessible without excavation. [1] Like hydrocarbon spills or oil spills (specifically, petrol spills) or certain chlorinated solvents may contaminate groundwater, and introducing the appropriate electron acceptor or electron donor amendment, as appropriate, may significantly reduce contaminant concentrations after a lag time allowing for acclimation. [1] An oil spill is the unintentional release of a liquid petroleum hydrocarbon into the environment as a result of human activity. [2] After a spill, hydrocarbons are subjected to physicochemical processes such as evaporation or photochemical oxidation which produce changes in oil composition. But the most important process acting on the spilled oil is biodegradation. [3] There are several ways to clean-up an oil spill in the given scenario and in situ treatment. Microbial Biodegradation through Methanogenesis, using the glycolysis pathway is one way. Bioremediation and Biotransformation methods endeavor to harness the astonishing, naturally occurring, microbial catabolic diversity to degrade, transform or accumulate a huge range of compounds including hydrocarbons such as oil. [1] Bacteria are minute unicellular microorganism, the smallest one having all the necessary protoplasmic equipment for growth and self-multiplication at the expense of available food stuff (Smith,1980) such as hydrocarbon fuel. Every bacterium is covered with a cell membrane known as the plasma membrane which separates it from the cytoplasm of the bacterial cell. Composed of phospholipids and proteins, the plasma membrane is the site of important enzyme systems, including the respiratory enzyme systems or cytochrome enzymes (Smith,1980). In regulating the passage of food materials, like oil, and metabolic by-products between the interior of the cell (where metabolic activities are carried on) and the