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I need help to clarify gram, acid fast and endospore technique unknown test - (Jul/05/2014 )

im going to have my first unknown bacteria test in Microbiology, we have to make gram test, acidfast test and endospore test. I know the steps to perform, but how do I recognize if each of the test was negative or positive? What should I actually see under the microscope, how many results are possible for each one? I'm so confused about this. Also How do I describe arrangment of groups of cells? What are the possibilities?  I attached the form that I will need to fill out, what should  be under the "shape of cell" and "arrangment of groups" can someone tell me example how it should look like? I have really no idea and will have unknown test on monday pls help
thank you

Attached Image

-florida2001-

You must have done this before during a class? Not?

Go to http://en.wikipedia.org/wiki/Bacterial_cellular_morphologies to start.

 

For the gram staining: its gram positive or gram negative.. you can google this , but you must have seen this before? Have you not done this during a practical session?

 

FOr the endospore test: its an endospore staining test I assume? Also something you can google very easly and something you should have done before.

 

I am not so sure what exactly you want to know? Dont you have a coursebook/slides from the teacher? You must have done these tests before?

-pito-

Yes we had only one lecture where we learned 3 staining method, then observed under the microscope, the images wasn't clear and it was hard to identify. I atached the sample of hte report I will need to fill out. I just need to know now how to fill the form, what description I put under cell arrangment and shape...just example. If I understand well under the gram test I just apply + or -..depends if the test will be positive or negative right?

-florida2001-

well look at the wiki page I gave you for the cell shape and arrangements! You just have to write down how they look (or draw it) and how they are "connected" to eachother.

(see the wiki)

 

For the gram stain: yes its either gram + or gram - . So based on the color you see yoiu just have to state its gram + or gram -

 

Whether its positive or negative depends on the bacterium you are looking at.

 

For the acid stain: if they stay red they retain the acid stain, so they are acid fast bacteria.

 

For the endospore stain; its to show if there are andospores or not. I dont know what stain you use but you can stain them green or red depending on the technique used.

-pito-

thank you 

-florida2001-