Microbiology (BIO 108) – Chap.27: Microbial Ecology

 

Learning Objectives

 

1.   Describe three examples of symbiotic relationships involving microbes.

 

2.   In general terms, what are biogeochemical cycles and why are they essential to the

     continuance and maintenance of life on earth?

 

3.   Describe, in specific terms, the accomplishments of microbes in the carbon cycle.

 

4.   Outline the nitrogen cycle, and explain the role of microbes in this cycle.  What is

      the importance of Rhizobium spp. and Azotobacter spp. in this cycle?

 

5.   Describe the following events in terms of what is being acted upon, what is being

      produced, and the organism(s) doing the conversion:  ammonification, nitrification,

      denitrification and nitrogen fixation.

 

6.   List the types of microbes that live in soil.  Where are they found in soil and in what

      numbers?

 

7.   Describe three examples of bioremediation with microbes.

 

8.   Describe the freshwater and seawater habitats of microbes.

 

9.   What is the role of microbes in determining water quality?  Describe how water quality

      is determined, the organisms used as indicators, and the public health significance of

      this kind of testing.

    

10. Describe the major steps in sewage treatment.  What is meant by primary treatment?

     secondary treatment?  Which parts of the process involve microbes?  Which do not? 

     Which part involves aerobic respiration?  anaerobic respiration?  In which part would

     oxygen not be a factor?

 

11. Is it true that microbes keep the earth habitable?  Defend your answer.

 

12. Define the boldface terms in chapter twenty-seven and add them to your vocabulary.