week 5: lab 13 (endospore staining)

Question 1

what are the common genera of endospore-forming bacteria?

Answer 1

Bacillus and the Clostridium

Question 2

what is the significance of endospore formation to bacteria?

Answer 2

-allows the bacterium to produce a dormant and highly resistant cell to preserve the cell’s genetic material in times of extreme stress
-Endospores can survive environmental assaults that would normally kill the bacterium.

Question 3

why do endospores appear green?

Answer 3

because of malachite green

Question 4

why do vegetative cells appear pink?

Answer 4

because of safranin

Question 5

what are the steps in endospore staining?

Answer 5

1. have a beaker half full of water on a hot plate and bring it to boil
2. obtain a clean slide
3. prepare smear with bacillus 24h and 1wk mixed into water drops
4. air dry, once dry, HEAT FIX
5. cover the smear with a piece of paper and put it over boiling water
6. soak the paper with malachite green for 5mins (add more stain as it dries)
7. remove the slide and allow it to cool
8. remove the paper towel and tip slide to rinse with distilled water
9. counterstain slide with safranin for 1min
10. rinse with distilled water and blot dry

Question 6

why are spores formed?

Answer 6

Certain bacteria make spores as a way to defend themselves.

Question 7

what are characteristics of spores?

Answer 7

-Spores have thick walls, resist high temperatures, humidity, radiation, desiccation, and chemicals
-Difficult to stain