(Solved): 9 Negative Staining A. Results 1. Draw the different types of microorganisms that were found in the ...

9 Negative Staining A. Results 1. Draw the different types of microorganisms that were found in the negative stain of the oral sample. How would you differentiate between oral streptococci, yeasts, and spirochetes in your sample? 2. Draw your slides made from bacterial cultures. Label the species under your drawing, and indicate the cell shape and/or arrangement. 1. What type of chromophore is associated with a negative stain? 2. What is an example of a negative stain? 3. What step normally associated with staining bacterial cells is omitted when the dimensions of cells are determined? Why? 4. What external bacterial cell structures can be demonstrated by a negative stain? Species: Species: Morphology: Morphology: Laboratory Report 10 Student: Date: Section: 4. Look up the term virulence factor if you do not already know its definition. Explain why the bacterial capsule is considered a virulence factor. 10 Capsular Staining A. Results 1. Draw cells that display a capsule from your stained slide of Klebsiella pneumoniae. Explain how the capsule is visualized without the use of dyes that adhere to a capsule. B. Short-Answer Questions 5. A student heat-fixes his smear intended for capsule staining. What result might the student expect? 1. What are two functions of the capsule or slime layer in bacterial cells? 2. What biological molecules can make up the bacterial capsule or slime layer? 3. What function does the capsule have for Streptococcus mutans?