General Microbiology Lab Exam 1 Possible Questions And Answers 100% Accurately Solved.

Bacillis Bacteria - correct answers Rod Shaped, Move easily (tail) Cocci Bacteria - correct answers Coccus, Not mobile. Streptococcus - correct answer Linear Row of coccus Diplococcus - correct answers Two linear cells of coccus Staphylocci - correct answers Cells grouped together of coccus Ubiquity of bacteria - correct answers Most are not pathogens... but actually normal flora and beneficial and essential to higher organisms. Immersion Oil - correct answers Oil forms a continuous lens system that limits the loss of light due to retraction. Colony - correct answers is a visible mass of cells usually resulting from a division of a single cell and number can exceed one billion from a single cell. Agar and petri dish - correct answers Agar media were easily manipulated, and could be added to rich broths to form a solid medium on which isolated colonies would develop. Petri dish protected the nutrient surface. Transferring broth to agar plate - correct answersFlame loops, culture tubes, raise the lid of the petri dish. Heat-fix slides. Aseptic Technique Rules - correct answersLab techniques: Disinfecting work area Flaming transfer tools Flaming culture tubes Used gloved hands Smear Preparation - correct answersBest to have one thin layer. Used: staphylococcus, streptococcus, and bacillus Gram Positive: - correct answersThick protein traps staining Peptiodoglycan Purple color Gram Stains: - correct answersPrimary stain: Crystal Violet Mordant: Gram's Iodine Counterstain: Safranin Decolorization: Alcohol Gram stain is an example of a differential stain. Used: Staphylococcus aureus, Escherichia coli, and Moraxella catarrhalis Pseudomonas aeruginosa Gram Negative: - correct answersThin layer of protein of Peptiodoglycan Pink color Staphylococcus aureus - correct answersPurple cocci Gram positive Motility - correct answersSome use flagella. Mobility is achieved by microbes using flagellum, which is an exquisitely designed motor. Escherichia coli - correct answersGram negative Pink rods Moraxella catarrhalis - correct answers Pseudomonas aeruginosa - correct answersGram negative pink rods Determining motility: - correct answers1. wet mounts 2. hanging drop slide 3. semisolid media Arrangement of flagella - correct answers Wet mount: - correct answersDrop of viable cells is placed on microscope slide and covered with a cover glass. Dries out quickly Hanging drop slide: - correct answersDrop of cells is placed on a cover glass, which is then placed over a special slide that has a concave depression. Cover slip is placed with petroleum jelly. Prevents drying out. Brownian Motion - correct answerscells or movement caused by currents under the cover glass. NOT MOVING. Semisolid media - correct answersStabbing medium with needle. If motile, they will swim away from the line of inoculation into uninoculated surrounding medium. Nonmotile bacteria will be found only along the line of inoculation. Two methods: - correct answers1. Pour plate technique 2. Streak plate isolation Both use dilution process. Goal: get single colonies. Pure cultures: - correct answersMust follow Koch's Postulates EXCEPTION: HIV/AIDS Only one kind of organism. Streak Plate: - correct answersMost common quadrant streak plate. Escherichin Cell: - correct answersCreamy White Pseudomunas aerogenis - correct answersGreenish Staphylococcus aureus: - correct answerslarge yellow/gold Endospore - correct answersPink outside with green inside. Spore Staining Technique - correct answersEndospore: Are able to with stand harsh conditions. Bacillus and Clostridium are common. They are extremely resistant to the harsh conditions which cause their initial formation - extreme survival is the goal. Malachite green - correct answersUsed to stain endospores. Acid Fast Stain - correct answersMain ones: Mycobacterium and Nocardia. Acid fast: stained by fuchsin Non-acid fast: stained by methylene blue Mycolic Acid - correct answersCell wall lipid, waxy material found in acid fast bacteria which prevents it from being stained by normal methods. Kenyan Acid-fast method - correct answersStain: Fuchsin Acid fast: pink or red Non: blue (dyed by the methane blue) Much safer method because it does not require heat.