Unit 10 Assignment 1
By Rebecca Abell
Many people believe that bacteria only cause disease and death. This is not technically true. While we have all suffered from some kind of an infection which we are told is caused some noxious form of bacteria, this is just a small part of what bacteria contribute to our lives.
First, it would be well to add a bit of science to be clear about what bacteria are. Defined most correctly, bacteria are a large group of one-celled microorganisms widely distributed in nature. Search any microbiological text book and you will see that there are thousands of different types of bacteria in the world, everywhere around us, although only about two thousand species of bacteria have actually been identified. On the most part, bacteria simply share the world with us and are of no specific harm to any human being. They are remarkable organisms for their simplicity of form, their efficiency of life and their rapid ability to reproduce. It has been said that it is possible for some species of bacteria, within the correct environment, to reproduce themselves in the span of about twenty minutes, although most do not reproduce quite so rapidly. . As far as we know, bacteria have been present upon the earth for billions of years and are generally considered to be one of the oldest and simplest forms of life. Most bacteria are very simple as far as their structure and function goes. They have a hard outer wall which is called a capsule; inside this capsule there exists a cell wall which guards the inner workings of the cell, called the cytoplasm. From within the cytoplasm comes the material from which the bacteria are able to reproduce. Interestingly enough, there are no organelles, which are small structures within cells that perform dedicated functions. As the name implies, you can think of organelles as small organs.
The organisms in the total coliform group are called indicator organisms. That is, if present, they indicate that there is a possibility, but not a certainty, that disease organisms may also be present in the water. When absent, there is a very low probability of disease organisms being present in the water. The ability of the total coliform test to reliably predict the bacterial safety of water relative to the hundreds of possible diseases that might be present is critical since it is impossible, in a practical sense, to check separately for every disease organism directly on a monthly or a quarterly basis. The presence of only total coliform generally does not imply an imminent health risk but does require an analysis of all water system facilities and their operation to determine how these organisms entered the water system.
Escherichia Coli (e-coli) is a specific species (subgroup) within the coliform family. They originate only in the intestines of animals and humans. They have a relatively short life span compared to more general total coliform. Their presence indicates a strong likelihood that human or animal wastes are entering the water system, and have a much higher likelihood of causing illness.
Microorganisms are widely used in the food industry to produce various types of foods that are both nutritious and preserved from spoilage because of their acid content. In the dairy industry, many products result from fermentation by microorganisms in milk and the products of milk. For example, buttermilk results from the souring of low-fat milk by lactic acid. The flavor is due to substances such as diacetyl and acetaldehyde, which are produced by species of Streptococcus, Leuconostoc, and Lactobacillus as they grow. A fermented milk product with a pudding like consistency is yogurt. Two bacteria, Streptococcus thermophilus and Lactobacillus bulgaricus, are essential to its production. After the milk has been heated to achieve evaporation, the bacteria are added, and the condensed milk is set aside at a warm temperature to produce the yogurt. Sour cream is produced in a similar way, using