micro lab report 1

8/8/2019 Micro Lab Report 1

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Lisas First Lab Experiment

Introduction:

Bacterial cell identification is such an important process. It helps us to identify the

different types of bacteria we are working with because there are so many different types out in

the world. By identifying the bacteria we can go on to find a name for it and be able to put it

into the class it belongs to. Bacteria can cause many illnesses and without the proper

identification there would be no way to treat an infection and we wouldnt be able to know

what it was resistant to.

The identification process consists of placing the specimen on the microscope slide with a

few drops of water stirring it until it creates a milky like substance on the slide. Next after the

specimen is dried you will set the slide with heat by waving the slide over a Bunsen burner a few

times back and forth. Next you will be placing a few drops of crystal violet on the specimen slide

to do a gram stain. You will wait for one minute then place it under water at a light flow to

avoid losing the specimen. Dry off the remaining water in a patting motion to avoid wiping the

specimen off. Now here we will begin the fun part which is placing the specimen slide under the

microscope so you can see the shapes of the bacteria.

You will begin using the red ringed microscope lens to magnify to 40x. After focusing the

lens to your eyes you will rotate the set of lenss halfway between the 40x and the 100x. Next

apply a small amount of oil onto the slide covering the specimen you will be viewing, next place

the 100x lens into the oil over the slide and begin the process of identifying the strain.

Methods:

I first began with the protocol called for in the Lab Handout 3 which called for cleaning

the slide, placing the specimen using the proper sterilization technique. I then set the specimen

with the heat, staining the slide using the crystal violet dye, drying the slide of excess water and

placing the slide under the microscope.


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I had 4 slides to work with. I performed two different types of tests on the slide

specimens, the Catalase test to see which of the four specimens were positive for Catalase and

the other test I performed was the gram staining by placing a few drops of crystal violet dye on

the slide.

Results:Colony Type 1 had a creamy white color, it was stained with gram negative dye and

tested positive for the catalase enzyme, the culture had a spindle shape to it the margins were

undulate with a convex elevation. It was large in size with a smooth shiny texture with an

opaque optical property. Upon examination under the microscope the specimen had a

staphylococci shape to it.

Colony Type 2 had a light brownish color, was stained with gram negative dye, and also

tested negative for the catalase enzyme. The culture had a circular shape before being placed

on the slide, the margins were entire with a raised elevation. It was small in size with a smooth

shiny texture; the optical property was non-pigmented. Upon examination under the microscope

I found there to be bacillus.

Colony Type 3 had a creamy white color with a yellow dot on the upper right corner, ithad a circular shape the margins are entire with a flat elevation. It was moderate in size with a

smooth shiny texture. The optical property is opaque. Tested positive for the catalase enzyme

Upon examination under the microscope I found it to be Staphylococci.

Colony Type 4 had a tan color non pigmented, an irregular shape, the margins were

curled with a convex elevation. It was moderate in size with a rough dull texture and the optical

property was opaque. Tested negative for the catalase enzyme. Upon examination under the

microscope I found there to be coccus.

Discussion:

The bacteria I had identified on my four different slides shocked me, they had very

similar characteristics of each other while in the Petri dishs but had such different results with


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the catalase enzymes and the different shapes that came out on the microscopes slides. I found

the Type 1 and the Type 2 to be the most intresting because they both tested negative for the

catalase enzyme and both had the staphylococci shape to them.


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Works Cited

Alexander, Strete 2001 Microbiology a Photographic atlas for the Laboratory

Talaro, 2008 sixth edition Foundations in Microbiology Basic Principles

Thompson, A, Lab Handout #3 Fall 2010

Thompson, a Lab Handout #4 Fall 2010

micro lab report 1

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