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1

Endospore normally repels stains used to visualize bacteria. What does that imply about the structure regarding its sensitivity to other harsh chemicals, like antibiotics and disinfectants?

  • Its hard to kill
    • It is has a strong ability to repel antibiotics and disinfectants

2

What is malachite green used for?

How is it forced into an endospore? 

What is malachite green used for?

  • Endospore staining

How is forced into an endospore? 

  • Heat, we used the heat from steam

3

What genera produce endospores?

Clostridium

Bacillus 

4

What conditions result in the formation of endospores?

  • Nutrient-poor environments 

5

When viewing cells via a simple stain or a Gram stain, what other structures might be confused with endospores ? Give at least two examples.

  • Granules 
     
  • Gas Vesicles

6

What is the purpose of negative staining?

  • See capsules around a bacteria by staining background of cells and not cells or capsules themselves 
     
  • Capsules stay intact
     
  • No heat fixation needed

 

7

How are dyes with negative charges related to the predominant charges on the surface of cells?

  • Surface of cells -> (-) charged
     
  • Dye and Cells and are repelled electrostatically, so the dye stains the background

8

Why is sodium thioglycollate or cysteine needed for the survival of certain prokaryotes?  

They reduce O2 to H2O, and anaerobes cannot handle the presence of O2

9

What are two enzymes that enable prokaryotes to "handle" oxygen?

  • Superoxide dismutase
     
  • catalase

10