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Question 1

bacteria phylogeny flaws

Answer 1

Inherited sequence similarities can be masked by continuing molecular evolution within groups
In some groups rates of sequence evolution appear to be higher than in others
Phylogenies may falsely group distantly related bacteria because they contain genes passed on by conjugation, transformation or transduction

Question 2

bacterial phylogeny pros

Answer 2

Small subunit rRNA genes show little evidence of horizontal transfer and so may faithfully record the evolutionary history of the organisms in which they occur

Question 3

Proteobacteria

Answer 3

Most diverse of all bacterial groups
Defined largely by similarities in rRNA sequences
Include many of the organisms that populate our expanded carbon cycle and other biogeochemical cycles
Includes an oxygenic photosynthetic bacteria and chemoautotrophs
Many have mutually beneficial ecological relationships with eukaryotic organisms
Pathogens that cause disease

Question 4

gram positive bacteria

Answer 4

Include organisms that cause and cure disease
Thick peptidoglycan walls
Gram positive bacteria called streptomycetes have provided us with tetracycline and numerous other antibiotics that combat infectious disease

Question 5

mutagenesis

Answer 5

add genetic variation (though UV or chemicals to induce mutation