please answer all the questions for microbiology : 1. Be able to draw and/or identify general...

90.2K

Verified Solution

Question

Biology

please answer all the questions for microbiology :
1. Be able to draw and/or identify general bacterial cell shapesand cell organizations
2. Know how to do a streak for isolation, and a spread plate andwhy you would do each
3. how to do a Gram stain, Endospore stain and acid fast stainand why you would do each.
4. Know the tools of the microbiologist and what they are usedfor
5. Be able to explain the results of the hand-washexperiment
6. Be able to identify and describe the results of theantiseptics/disinfectants, antibiotics experiment and interpret theresults
7. Know what aseptic technique is and how to exhibit aseptictechnique

Answer & Explanation Solved by verified expert

4.3 Ratings (707 Votes)

1 On the basis of their morphology and shape bacteria can becategorized as UnicellularBacteriaSpirochaetesMyxobacteria and Filamentous BacteriaActinomycetesUnicellular bacteria arefurther divided intoCocci or coccus for a single cellare round cells sometimes slightly flattened when they areadjacent to one anotherBacilli or bacillus for a singlecell are rodshaped bacteriaSpirilla or spirillum for a singlecell are curved bacteria which can range from a gently curvedshape to a corkscrewlike spiral Many spirilla are rigid andcapable of movement A special group of spirilla known asspirochetes are long slender and flexible2Procedure of Spread Plate Techniqueprepare a dilution series from a samplePipette out 01 ml from the appropriate desired dilution seriesonto the center of the surface of an agar plateDip the Lshaped glass spreader into the alcoholFlame the glass spreader hockey stick over a BunsenburnerSpread the sample evenly over the surface of agar using thesterile glass spreader carefully rotating the Petridish underneathat the same timeIncubate the plate at 37C for 24 hoursCalculate the CFU value of the sample Once you count thecolonies multiply by the appropriate dilution factor to determinethe number of CFUmL in the original sampleUses of Spread Plate TechniqueIt is in use for viable plate counts in which the total numberof colony forming units on a single plate is enumeratedIt is used in order to calculate the concentration of cells inthe tube from which the sample was platedIt is routinely used in enrichment selection and screeningexperimentsProcedureSterilize the inoculating loop in the bunsen burner by puttingthe loop into the flame until it is red hot Allow it to coolPick isolated colony from the agar plate culture and spread itover the first quadrant approximately 14 of the plate usingclose parallel streaks or Insert your loop into the tubeculturebottle and remove some inoculumImmediately streak the inoculating loop very gently over aquarter of the plate using a back and forth motion seearea 1 in the figure belowFlame the loop again and allow it to cool Going back to theedge of area 1 that you just streaked extend the streaks into thesecond quarter of the plate area 2Flame the loop again and allow it to cool down Going back tothe area that you just streaked area 2 extend the streaks intothe third quarter of the plate area 3Flame the loop again and allow it to cool Going back to thearea that you just streaked area 3 extend the streaks into thecenter fourth of the plate area 4Flame your loop once againImportance of streakingTo help produce isolated colonies of an organism mostlybacteria on an agar plate This is useful when we need to separateorganisms in a mixed culture to purifyisolate particular strainfrom contaminants or when we need to study the colony morphologyof an organismIdentify the organism biochemical tests to identify bacteriaare only valid when performed on pure cultures3Gram Stain ProcedurePlace slide with heat fixed smearon staining trayGently flood smear with crystalviolet and let stand for 1 minuteThan tilt the slide slightly andgently rinse with tap water or distilled water using a washbottleGently flood the smear with Gramsiodine and let stand for 1 minuteTilt the slide slightly and gentlyrinse with tap water or distilled water using a wash bottle See Answer

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member