1. Why do we heat fix the bacteria to the slide before staining? - ✔✔So the bacteria will hold the stain better.
2. A basic dye has the color in
... [Show More] the
_____________ ion - ✔✔Positive
3. All bacteria have a slight negative charge; a basic dye has the color in the positive ion. Opposite charges attract. This is the principle behind: - ✔✔direct staining
4. Why do gram positive bacteria appear purple after staining? - ✔✔The alcohol and acetone dehydrates
the many layers of peptidoglycan
5. A bacterial that has one flagella is called what? - ✔✔Monotrichis.
6. A bacteria that has flagella all around its outside coat (surrounded by flagella) is called what? - ✔✔Peritrichas.
7. A bacteria that has a flagella that is coming out both ends is called what? - ✔✔Lophotricus.
8. A bacteria that has a single flagella at both poles is called what? - ✔✔Amphitrichous.
9. What are the steps for staining a capsul? - ✔✔1) put five loops of bacteria on a slide from a broth mixture
2) Let mixture dry on slide.
3) add two drops of crystal violet, spread on slide.
4) let slide dry for 1-2 min.
5) flood slide with copper sulfate let sit for 20 seconds.
6) Shake off excess copper sulfate.
7) Blot slide dry.
10. What are the characteristics of a gram positive cell wall? - ✔✔1) Thick dense wall
2) contains high levels of peptidogylcan.
3) Wall is composed of teichoic acids
11. What are the characteristics of a gram negative cell wall? - ✔✔1) The cell wall only contains 2-3 layers of peptidogylcan.
2) Phospholipids are found mainly in the inner layer of the outer membrane
12. What are the steps to gram stain a bacteria? - ✔✔1) Stain bacteria with crytal violet
2) Then treat bacteria with gram's iodine solution.
3) Add grams decolorizer
4) Add safranin.
13. What type of charge do bacteria have? - ✔✔Bacteria have a slightly negative charge.
14. What are the basic dyes? - ✔✔the basic dyes are methylene blue, crystal violet and safrain.
15. What is a direct stain? - ✔✔The bacteria will hold the stain inside of the cell.
16. What is an indirect stain? - ✔✔The bacteria will not let the stain come into its cell, so the stain colors around the bacteria.
17. What are the steps to directly stain bacteria? - ✔✔1) Put one drop of water on a slide
2) aseptically remove some bacteria and mix it into the water.
3) Spread the mixture over the slide.
4) Let slide dry.
5) Pass slide through flame 12 times to heat fix bacteria.
6) Cover slide with safrain and let sit for 1 minute.
7) Wash slide.
8) Blot slide dry.
18. What are the steps to indirectly stain bacteria? - ✔✔1) Put one drop of nigrosin on slide.
2) Aseptically add a small amount of bacteria and mix with dye.
3) Use another slide to spread bacteria on slide.
4) Let slide air dry.
5) Put slide under microscope with oil and view.
19. Why do we NOT wash of the stain when we are making an indirect slide? - ✔✔The stain is not affixing itself to the bacteria, rather it is just hanging out around the outside of the bacteria. If we washed the slide with water all the stain would be washed away and we would not be able to see our bacteria when we put it under the slide.
20. What is a coccus? - ✔✔One circle shaped bacteria.
21. What is a diploccoccus? - ✔✔A chain of only two bacteria.
22. What is a streptococcus? - ✔✔A chain of several bacteria.
23. What is a tetrad? - ✔✔Four bacteria grouped in a square shape
24. What does a staphylococcus arrangement look like? - ✔✔Grape like clusters of bacteria
25. What does a sarcina arrangement look like? - ✔✔Looks like a tetrad, but it has four more bacteria behind the original four, so it will be a three dimensional square shape totaling 8 bacteria.
26. What is a bacillus - ✔✔A rod looking shapped bacteria
27. What is a streptobacillus? - ✔✔Several rod shaped looking bacteria chained together.
28. What is a coccobacillus? [Show Less]