1. Introduction

Introduction
The world is filled with bacteria, both helpful and harmful. We use them in our daily lives for food and other products. Some are harmful which can cause severe diseases and in severe cases, death. Here are some examples and types of helpful bacteria. Lactobacillus is gram-positive and it is rod shaped. It is used in dairy products such as milk, fermented foods and slide form part of our oral, intestinal and vaginal microflora. It is know for its ability to utilise lactose and produce lactic acid, as a metabolic byproduct. Thus, it is an important ingredient for preparing fermented foods. They are also an important part of probiotic formulations. (Clapper T. , 2011) Bifidobacterium is gram-positive, branched and rod-shaped. It is present in the gastrointestinal tract of humans. It produces acetic aced. This inhibits the growth of pathogenic bacteria by controlling pH levels in the intestines. Escherichia coli (E.coli) is gram negative and rod shaped. it is part of the normal microflora of small and large intestines. It helps break down indigested monosaccharide sugars and thus aid digestion. It produces vitamin K and biotin which are essential for a variety of cellular processes. Although, certain strains of E.coli can cause severe toxicity, diarrhoea, anaemia, kidney failure and death. Streptomyces is gram-positive and filamentous. They are widely found in soil water and decaying matter. It plats an important role in soil ecology by bringing about the decomposition of organic matter present in soil. As a result, they are being explored as agents for bioremediation. (Dawkins, 2013)

Here are some examples and types of harmful bacteria. Mycobacteria is neither gram-positive or gram-negative (due to high lipid content) and it is rod shaped. It is found in water and food. They are obligate parasites and cannot survive in their free form. They are the causative agents for tuberculosis and leprosy. Clostridium tetani is gram positive and box shaped. It is found in soil, skin and the gastrointestinal tract. It enters the body through a wound, replicates there and releases toxins, namely tetanospasmin and tetanolysin. These lead to muscular spasms and respiratory failure. (Bjornsson, 2012) Yersinia pests is gram negative and it is rod shaped. It can only survive within the host, namely rodents and mammals.  It causes bubonic and pneumonic plague. A skin infection with this leads to the bubonic from characterised by malaise, fever , chills and even seizures. An infection in the lungs can lead to difficulty breathing, fever and coughs. Helicobacter pylori is gram negative and rod-shaped. It colonies the mucosal lining of the human stomach. It is the leading cause for gastritis and peptic ulcers. It produces cytoxins and ammonia which damage the stoma epithelium leading to abdominal pain, nausea, vomiting, and bloating. It is present in half of the world’s population, however, most of them are asymptomatic while only a few develop gastritis and ulcers. Finally, Bacillus anthracis is gram-positive and rod-shaped. It is found in soil. Sores, fever, headache, abdominal pain, nausea, diarrhoea etc. are the most common symptoms. (Hakansson. A, 2013)

Our team wants to find out why are people falling sick in SST. We want to find out the type of bacteria forms and how we can prevent it. With our research we can show the students of SST that what kind of bacteria is present when they come into contact with staircase railing, canteen table and lockers to name a few. 


Independent Variables
The places in SST where we collect our data. 


Dependent Variable
The amount of harmful bacteria. (e.g. E.coli, Staphylococcus)


Constant
  1. The number of samples
  2. The type of cotton swab
  3. The method used to examine the bacteria
  4. The way the bacteria is handled
  5. The duration of swabbing at each location
  6. The duration of incubation for all samples
  7. The number of petri dishes
  8. The amount of nutrient broth poured into the agar plates
  9. The amount of nutrient broth the cotton swab is dipped into.

No comments:

Post a Comment