Section 4, Part C

Question 1

What key roles do prokaryotic organisms play in basic ecosystem function?

Answer 1

1. Decomposers
2. Primary Producers
3. Nitrogen Fixation.

Question 2

What are examples of prokaryotes in symbiotic relationships with other organisms?

Answer 2

Rhizobia and legumes: Rhizobia are the only nitrogen fixing bacteria that live in a symbiotic relationship with legumes. The bacteria fix the free nitrogen into a usable fixed nitrogen, which is a basic macronutrient that the plant needs to survive.

E. Coli and Humans: E. Coli inside intestines are mutualistic. They are able to to get food in a preferable living condition while benefiting hosts by helping produce vitamin k2 and aiding in the prevention of the establishment of pathogenic bacteria within intestine.

Question 3

Why are some prokaryotes called extremophiles? In what environments do they live?

Answer 3

Extremophiles are organisms that thrive in physically or geochemically extreme conditions that are considered harmful to most other organisms.

Halophiles–highly saline environment
thermophiles–high temperatures ( ex: hydrothermal vents)
psychrophiles–low temperatures