ELN Lab 1 5-14.docx

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Department
Microbiology and Cell Science
Course
MCB 3020L
Professor
ashgar
Semester
Fall

Description
Chloe Evetts (8990-4674) Cameron Jacobs May15,2013 MicrobesintheEnvironmentandonYou Purpose: Microorganisms are of abundance and located virtually everywhere on planet earth. These organisms, much smaller than the eye can perceive, are considerably diverse. As potentially pathogenic, such as the carbapenem-resistant Enterobacteriaceae (CRE) (figure a), and/or beneficial, like the gut flora of the human intestines (figure b), microorganisms need to be studied in depth to understand what is causing diseases and what is helping animals thrive. Studying microorganisms involves the application of various aseptic techniques which allows us to work with non-contaminated specimen. The purpose of this lab is to learn the various aseptic techniques that come with studying bacteria, apply those techniques to collecting microbial specimen from the air, from our body, and from around the room, and properly culture the bacteria on agar plates. Figure Figure b Hypothesis: Due to the countless number of microorganisms present at any given time, exposure of the agar plates to the air will allow species to accumulate on the plate. Incubation of these plates will promote growth and colonies can then be studied. Sterile swabs will also easily collect numerous specimen from around the room and on our body. Incubation of these plates will promote growth and colonies can then be studied. Procedure: Five totalagarplates wereused,threeof whichwerebrainheart infusionagar (BHI) plates,capableof growingbacteria,andtwoofwhichwere PotatoDextroseAgar (PDA) plates,capableof growingfungiandyeast.Eachplate was labeledonthebottomwitha permanent markerandour initials,date,mediatype.OnePDAandoneBHIplate were labeled“openlid” (FigureC),oneBHIplate withalinedrawnthroughthemiddlewas labeledwithaselectedbodypart oneachside,one BHIplate withaline drawnthrough themiddlewaslabeledwithdifferentselectedareasof theenvironment oneachside,and one PDAplate withalinedrawnthroughthemiddlewaslabeledwithdifferentselected dustyareasoneachside (figureD). Figure c Figure d The open lid plates were left open until the end of class in order to maximize specimen collected. The body plates were swabbed with samples taken from the cheek and from behind an ear. The environment plates were swabbed with samples from a cell phone and a shoe. The dusty plates were swabbed with samples from the sink handle and the sink drain. The plates were then closed, making sure to tape the PDA plates and inverting only the BHA plates, and then placed in the incubator. Results: In the Air: Circular, irregular and punctiform Sample left open for 1 hour In the Environment: Left: shoe Right: cell phone Circular, irregular, filamentous, and punctiform On Me: OnMe: Left: cheek swab Right: behind the ear Punctiform Discussion: After letting our petri dishes incubate for 48 hours, it was shocking how many different colonies grew from our samples. Our hypothesis was correct in that incubating plates will indeed promote the growth of many different microorganisms. There are a multitude of different organisms present all around us, including our cell phones, shoes, cheeks and behind our ears. The most shocking was the amount of growth present on the dish that was just left open in the air. There was some variety in colors and sizes amongst the different samples. Some were yellow, others white, some slightly translucent. There were also some fungi present. Between the different samples, the shoe sample provided the most abundant amount of different bacteria. It is very interesting to see the abundance of different bacteria and microbes that live all around us on things we touch everyday. Glossary: • Nosocomial: Hospital Acquired infection (HAI) • Aseptic: Free from contamination caused by harmful microorganisms • Brain heart infusion agar: enriched non-selective medium for the isolation and cultivation of most anaerobic bacteria and other fastidious microorganisms • Potato Dextrose agar: nonselective medium for the cultivation of yeasts and molds • Antibiotic: agent that inhibits bacterial growth or kills bacteria. • Archaea: The Archaea constitute a domain of single-celled microorganisms. These microbes have no cell nucleus or any other membrane-bound organelles within their cells. • Athlete’s foot: Athlete's foot is an infection of the feet caused by fungus. The medical term is tinea pedis. Athlete's foot may last for a short or long time and may come back after treatment. • Bacillus subtilis: Bacillus subtilis, known also as the hay bacillus or grass bacillus, is a Gram-positive, catalase-positive bacterium. • Bacteria: Bacteria constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. • Bacteriodes: Bacteroides is a genus of Gram-negative, bacillus bacteria. Bacteroides species are non-endospore-forming, anaerobes, and may be either motile or non-motile, depending on the species. The DNA base composition is 40-48% GC • Bacteriophage: A bacteriophage is a virus that infects and replicates within bacteria. The term is derived from 'bacteria' and the Greek φαγεῖν phagein "to devour" • Biodiversity: the degree of variation of life forms within a given species, ecosystem, biome, or planet. • Chicken pox: Chickenpox is a viral infection in which a person develops extremely itchy blisters all over the body. It
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