Exercise 1 oil-immersion objective,and use the fine adjustment to bring specimen into proper focus. e.To remove specimen,turn course adjustment knob in the direction tha makes the objective travel away from the slide.Remove microscope slide eaeswhestscheacpostaaec 10X 40X 60X Oil Immersion 100X SECOND SESSION FOCI:Gram Stain Technique,Characterization of Isolated Colonies A.Colony Morphology of Isolated Colonies and Pure Cultures >> 1.Check the TSA medium plates that were inoculated via the streak plate method for the presence of separate distinct colonies.Describe the cultural characteristics of these isolated colonies as to their size and shape. 2.Pure cultures of individual microorganisms are obtained by picking up a separated colony with a sterile inoculating needle or loop and streaking another plate of medium with this material.After 24 hours of incubation one should have an entire plate of one specific microorganism,and such pure cultures are then used to perform various tests and inoculations so that the bacterium can be identified according to its enzymaticaction on various substrates. 3.Prior to determining the metabolic activity of unknown bacteria, microorganisms are first identified based upon their morphology,namely their staining reaction,size,shape,pigment production,motility,and presence of capsules or spores.Gram stain several of the isolated colonies from the M-H streak plate and attempt to identify them morphologically 4.Pure cultures of Staphylococcus epidermidis and Pseudomonas geruginosa on M-H media will be available for student examination. Describe the cultural colony characteristics of these microorganisms and look for pigment production.Gram stain these bacteria and identify their microscopic morphology. Staphylococcus epidermidis Pseudomonas aeruginosa B.Differential gram stain >>> Prepare a smear of Escherichia coli on one end of the slide and a smear of file:///Desktop/clown/Microb Lab Web 2001/Exercise1/exercise1b.htm(5 of6)[8/3/00 :9:54 PM] oil-immersion objective, and use the fine adjustment to bring specimen into proper focus. e. To remove specimen, turn course adjustment knob in the direction that makes the objective travel away from the slide. Remove microscope slide and always clean lens with lens tissue before proceeding to examine the next specimen. 10X 40X 60X Oil Immersion 100X SECOND SESSION FOCI: Gram Stain Technique, Characterization of Isolated Colonies A. Colony Morphology of Isolated Colonies and Pure Cultures >>>>> 1. Check the TSA medium plates that were inoculated via the streak plate method for the presence of separate distinct colonies. Describe the cultural characteristics of these isolated colonies as to their size and shape. 2. Pure cultures of individual microorganisms are obtained by picking up a separated colony with a sterile inoculating needle or loop and streaking another plate of medium with this material. After 24 hours of incubation, one should have an entire plate of one specific microorganism, and such pure cultures are then used to perform various tests and inoculations so that the bacterium can be identified according to its enzymatic action on various substrates. 3. Prior to determining the metabolic activity of unknown bacteria, microorganisms are first identified based upon their morphology, namely their staining reaction, size, shape, pigment production, motility, and presence of capsules or spores. Gram stain several of the isolated colonies from the M-H streak plate and attempt to identify them morphologically. 4. Pure cultures of Staphylococcus epidermidis and Pseudomonas aeruginosa on M-H media will be available for student examination. Describe the cultural colony characteristics of these microorganisms and look for pigment production. Gram stain these bacteria and identify their microscopic morphology. Staphylococcus epidermidis Pseudomonas aeruginosa B. Differential gram stain >>>>> Prepare a smear of Escherichia coli on one end of the slide and a smear of Exercise 1 file:///C|/WINDOWS/Desktop/clown/Microb Lab Web 2001/Exercise1/exercise1b.htm (5 of 6) [8/31/2002 4:29:54 PM]