Bacterial Diversity Lab

Bacillus, Coccus, and spirillum are the three main kinds of bacteria. Bacillus are rod shaped. Cocci are spherical shaped. Finally spirillum are spiral shaped.

See Table 1 and Flow Chart 1 for results of Bacteria # 1 and Table 2 and Flow Chart 2 for results of Bacteria # 2.

Bacteria is a single celled organism, bacteria have evolved to thrive in almost any environment and can be found in almost any substance/surface and also in the human body, only 1% of bacteria is actually harmful.

|MSA Agar |For organisms that are |Isolates for mannitol fermentation |Yellow color change in |Staphylococcus aureus |

Citrobacter Freundii is a species of bacteria that can be potentially harmful to humans. It is known to cause meningitis by protruding into the brain and replicating itself (1). The Citrobacter species has also been found as a cause of some urinary tract infections, diarrhea, and even gastrointestinal diseases and symptoms (3). C. Freundii can be located in a wide variety of soils and water (3). Lastly, it is also the cause of many nosocomial infections due to its presence in water (1).

Bacteria are prokaryotic, and if you were to observe the two cells under a light microscope, you could distinguish their differences. The biggest distinguishment you can make while carefully observing the two cells, is the lack of a nucleus in a prokaryotic cell as compared to a eukaryotic. Prokaryotes also lack any membrane-bound organelles.

The science of identifying these organisms based on known characteristics is termed bacterial taxonomy. Where each species is assigned to a genus which then follows a level of hierarchy using ranks (family, suborder, order, subclass, class, division/phyla,

Bacteria are small, unicellular prokaryotic microbes. They have many morphologies, which include rod-shaped, spherical, spirals, helices, stars, cubes, and clubs. Classification of bacteria begins with either aerobic (requiring diatomic oxygen for growth) or anaerobic (not requiring O2 for growth). Bacteria can simply be narrowed down to gram positive (organism that stains purple or blue by Gram stain) or gram negative (organism that stains red or pink by Gram stain). Many physical and nutritional factors influence bacterial growth. Physical factors include temperature (psychrophiles, thermophiles, and mesophiles), pH (neutrophiles, acidophiles, and alkalinophiles), O2 concentration (aerobic

Figure 3. The isolated colonies from figure 2 are viewed under the microscope at the 100x objective after gram staining. In this figure, you can see both gram-negative and gram-positive microorganisms. The gram-negative are the Rhodospirillaceae and they are pink rod-shaped bacteria. The

After the gram staining of the unknown bacteria, observation under oil immersion using a bright field microscope at 1000x of the shape, Arrangement, color and type of gram reaction of the microbes was

Bunches of spherical shapes (Staphylococci) looks mosaic, Streptobacillus, the veined structure is more pronounced, Vibrio shapes (slightly curved, but not distinctly spiral)

The students will be able to analyze the size, margins, elevation, and color of their bacteria.

My bacterium was swabbed off of a coke machine button. I decided to swab this particular spot because I believed there would be numerous bacteria found there since I see people everyday punching a button to get a cool beverage during breaks in between classes every day. To my surprise, there was only one colony that grew on the agar we had smeared it on. This was very surprising to me because I was sure there would be more bacteria growing on the machine rather than only one colony.

Life on this planet began with microorganisms. Through millions of years microorganisms have found ways to successfully adapt and survive. These adaptations have created a wide biodiversity, allowing them to basically populate in all places. Why are these microbes so important? Because they shape the history of our world. Some microbes can be deathly to humans while some others are favorable, for example, bacteria that lives in the gut of both humans and animals and helps during the process of digestion (Alfred Brown & Heidi Smith, 2006). Understanding these interactions help scientists to find ways to protect humans from potential deathly pathogens. In order to observe microbes, microscope proficiency and microorganisms’ identification are crucial skills in a microbiology lab. During this laboratory session, samples of environmental and human organisms were inoculated into two different rich media and incubated to their according temperature. After this, appropriate use and calibration of the microscope was performed. Lastly, morphology and size of different species of bacteria, algae, fungi and protozoan were recorded.

Bacteria vary greatly in terms of their characteristics and morphology. Colonies can be classified according to their colour, form, elevation, margin and size. Pure cultures of microorganisms