Prokaryotes include two domains with enormous diversity pt. 2

microbes

have a crucial roll in the carbon cycle

1. they decompose organic matter in soil + water, releasing CO2

   1. some absorb CO2

nitrogen fixation

chemical reactions in which prokaryotes convert atmosphere nitrogen (N2) into forms that plants and other organisms can absorb, such as ammonia (NH4+)

nitrogen

component of protein, DNA

1. the only organisms that can use { } directly are a few species of bacteria and archaea

   1. some live in soil or water

   2. ex. rhizobium lives on clovers

antibiotics

{ } can kill normal microbes, allowing the harmful ones to take their places

1. normal microbes divide to fix this

virulence

describes the degree to which bacterium harms it’s host

1. pili and slime capsules contribute to { }

bacterial toxins

Exotoxins and endotoxins are both considered

exotoxins

toxic proteins that difuse out of a bacterial cell

1. ex. staphylococcus aureus —> toxic shock, infections in the skin and sinuses

   clostridium botulinum —> botulism

endotoxins

part of the cell itself

1. specifically outer membrane of the gram-negative cell wall

2. only released when the cell dies

3. ex. E coli

humans

what species has exploited the metabolic talents of microbes?

1. foods, biotech, waste and waste water treatment