Lab Practical
Match each term to the best definition. 1. Lophotrichous 2. Amphitrichous 3. Selective media 4. Motility media
1. Bacteria with numerous flagella at one end 2. Bacteria with a single flagellum at each end 3.Agents that prohibit the growth of some microbes 4. Gel that prevents the diffusion of some microbes
Match each term to the best description. 1. Agent that kills bacterial upon exposure. 2. Agent naturally produced by microorganisms. 3. Agent that slows the growth of bacteria. 4. Agent artificially synthesized or manipulated from other products.
1. Bactericidal 2. Antibiotic 3. Bacteriostatic 4. Antimicrobial
Match each term with the best description. 1.Identifies metabolic properties of microbes 2. Enzyme that mediates the breakdown of hydrogen peroxide 3. Anaerobic metabolism that produces acids, alcohol, and gases 4. Anaerobic metabolism that produces acetoin 5. Metabolic process resulting in oxygen and peroxide by-products
1. Biochemical test 2. Catalase 3. Mixed acid fermentation 4. Butanediol fermentation 5. Aerobic respiration
Match each term to the best description. 1. Liquid media used to increase the number of microorganisms. 2. Solid media used to isolate microbes. 3. Normal flora bacteria used for studies involving osmotic pressure, antibiotic resistance, and biofilms. 4. Clump of genetically identical microorganisms. 5. Single-celled fungi used for studies involving fermentation, genetics, and aging. 6. Instrument used for spreading microorganisms across a streak plate.
1. Broth 2. Agar plate 3. Staphylococcus epidermidis 4. Colony-forming unit (CFU) 5. Saccharomyces cerevisiae 6.Inocculation loop
Match each term with the best description. 1. Describes individual colonies on a plate's surface 2. The number of individuals doubles each generation 3. Cloudiness of a fluid caused by large numbers of particles/organisms 4. The measure of the light intensity absorbed by a sample 5. Asexual reproduction resulting in two daughter cells
1. Colony-forming unit 2. Exponential growth 3. Turbidity 4. Absorbance 5. Binary fission
Order the steps of Gram staining into the proper sequence.
1. Crystal violet applied to heat-fixed cells 2. Iodine is applied to the slide 3. Decolorize dehydrates the Gram-Positive cell walls 4. Safraninis applied to the slide
Order the steps for performing a dilution series.
1. Determine the dilutions of the dilution tubes 2. Determine which plate is the countable plate 3. Calculate the concentration of the original tube
Match each antibiotic to its mode of action. 1. Targets DNA gyrase, preventing DNA replication within a cell. 2. Disrupts cell wall stability, eventually leading to cell lysis. 3. Binds with bacterial ribosomes to prevent cell growth and cell division.
1. Nobobiocin 2. Penicillin 3. Gentamicin
Match each term with the best description. 1.A spherical bacteria with a diameter of approximately 0.5 µm 2.Rod-shaped bacterial cells linked to form a chain 3. A dye that stains only the cell leaving the background colorless 4. Acidic stain repelled by the cell's surface 5. Mesh-like polymer present in bacteria cell walls
1.Coccus 2. Streptobacilli 3. Direct Stain 4. Congo red 5. Peptidoglycan
Match each term to the best description. 1. Microorganisms found in or on the human body on a semi-permanent basis without causing disease 2. Process of growing microbes in a controlled environment 3. Process of melting and adding agar to Petri dishes 4. Population of living microbes, in sufficient numbers, for use in experiments
1.Normal flora 2. Incubation period 3. Plate Pouring 4.Active cultures
Match the term with the definition. 1. Eyepiece that is typically 10X or 15X magnification 2. Calculated by multiplying the magnification of the ocular lens with the objective lens 3. Visible area of a slide that can be observed 4.Distance range that is in focus at a given time 5. Held by the turret closest to the stage, and range in power from 4x to 100x magnification
1.Ocular lens 2. Total Magnification factor 3.Field of view 4. Depth of view 5. Objective lens
Cultures should be soaked in bleach for _____ before disposal.
2 hours
Plates with _____ colonies per plate are used to calculate CFUs.
30-300
Methyl red is a pH indicator that turns red in _____ conditions.
Acidic
_____ is an example of a direct stain.
All of the above: Crystal violet, Methylene blue, Safranin
_____ is a form of functional media used to identify unknown microbes.
All of the above: Differential media, Enriched media, Selective media
Mixed-acid fermentation produces _____.
All of the above: acetic acid, ethanol, hydrogen gas
The inoculation loop must be sterilized _____ when creating a streak plate.
All of the above: before use, between use in each quadrant, after completing all quadrants
Bacteria move by _____.
All of the above: flagella, axial filaments, slime secretions
Normal flora are found _____ of healthy individuals.
All of the above: inside mouth, on skin, within the intestines
Aseptic techniques are necessary to _____.
All of the above: maintain safety, isolate pure cultures, prevent the spread of unwanted microbes
Many microbiology lessons require _____.
All of the above: plate pouring, active time, incubation time
_____ are rod-shaped becteria 0.5 - 20 µm in length.
Bacilli
Agar plates should be labeled on the _____.
Bottom
Novobiocin is a bacteriostatic, narrow-spectrum antibiotic that targets _____ in some Gram-positive bacteria.
DNA gyrase
_____ washes dyes from Gram-negative bacteria.
Decolorizer
The _____ sits below the stage and varies the field for viewing the specimen.
Diaphragm
_____ media contain an indicator that enables differences between microbes to be visualized.
Differential
_____ is a rod-shaped bacteria important to the study of genetics and evolution.
Escherichia coli
Binary fission is a method of sexual reproduction where a single cell (parent cell) will split into four cells (daughter cells).
False
Laboratory-style incubators are required for culturing the microbes used in HOL lessons.
False
The depth of field is independent of the total magnification factor.
False
The effective zone of inhibition is the same for all antibiotics.
False
Catalase neutralizes the harmful effects of _____.
Hydrogen peroxide
Biochemical tests are designed to identify _____ properties of microbes.
Metabolic
To determine the number of CFUs in the original culture, the number of colonies on the viable plate is _____ the total dilution factor of that plate.
Multiplied by
The mold that Alexander Fleming observed preventing bacterial growth was _____.
Penicillium notatum
_____ bacteria have flagella distributed all over the surface of the cell.
Peritrichous
Motility media is a _____ used to detect bacterial movement.
Soft gel
_____ are bead-like chains of spherical cells.
Streptococci
A compound microscope is a type of optical microscope.
True
Agar is a solid media used in both slants and plates.
True
Bacteriostatic antibiotics cause an inhibition of growth rather than cell lysis and death.
True
Butanediol fermentation produces weaker acids than mixed-acid fermentation.
True
Gram-positive cells have a thick outer cell wall composed of peptidoglycan.
True
Many types of bacteria have gained resistance to antimicrobials at an astonishing rate.
True
Morphology can be used to identify microorganisms with or without the use of a microscope.
True
Negative staining results in a colorless cell on a stained background.
True
Identify each statement as true or false.
True: Goggles, gloves, and face mask should be worn at all times when handling active cultures, Expose to bright light can inhibit microbial growth, microbiology lessons often require incubation periods and active cultures False: Low incubation temperatures decrease the amount of time required for microbial growth, most microbiology lessons can be completed in 1 to 2 hours, normal flora are pathogens typically found in or on the human body
Identify each statement as true or false.
True: Open tubes and vials should be tilted away from mouth and nose, Aseptic techniques are designed to prevent the spread of microorganisms beyond the intended working environment, media containers should be stored away from children and pets False: Work surfaces should be sterilized with soap and water, plates should be incubated agar side down, the caps and lids of media containers should be placed on counter tops when working with cultures
Determine whether each statement is true or false.
True: MR-VP broth contains nutrients and buffers, fermentation occurs when carbohydrates are metabolized anaerobically False: Biochemical test provide more generalized information than doing morphology observations, All aerobic microbes lack the enzymes catalase
Categorize each statement as True or False.
True: Functional media are used to identify unknown microbes, Motility test are conducted on soft gel media False: All motile bacteria have one or more flagella, Clear media is a positive test result for motility
_____ is a positive test result when using motility media.
Turbidity
Voges-Proskauer Methyl Red Catalase
VP: Barritt's reaction & Butanediol fermentation MR: Low pH & Mixed acid fermentation C: Peroxide & Aerobic respiration
_____ is a solid gel used to grow microbes in the laboratory.
agar
Label the parts of a microscope
look at diagram
Penicillin disrupts the formation of bacterial cell walls by inhibiting the formation of _____ cross-links.
peptidoglycan
Gentamicin binds with bacterial _____.
ribosomes