phototrophs are organisms that can synthesize all the compounds needed for growth. (can be grown on minimal medium)
auxotrophs cannot synthesize one or more of the necessary compounds for growth
3 ways bacteria transfer genetic information...
conjugation between F+x F- results in what types of exconjugants?
F+x F- results in two F+ cells
process: pilus, one strand of plasmid moves across, DNA complement synthesized on both single strands, cells separate
how does F+ cell become Hfr cell?
F factor is integrated into the bacterial chromosome
Hfr x F- results in what types of exconjugants?
Hfr x F- results in an Hfr cell and an F- cell with extra genes
process: bacterial chromosome integrates F factor and becomes Hfr, Hfr able to conjugate with F- cell and transfer some genes, F factor does not transfer
what is an F' cell?
when the F factor that had been integrated into the Hfr chromosome excises it brings a few genes along with it
F' x F- what types of exconjugants?
F' and a merozygote (also F')
process: F factor of Hfr cell excises from chromosome bringing a few genes along, now considered F', when crossed with F-, the F factor along with the excised genes are transferred and the recipient cell now may have two copies of those genes, a merozygote considered partially diploid
F factor plasmids vs R plasmids
F factor plasmids confer fertility; genes for sex pilus
R plasmids have resistance transfer factor (RTF) that codes for plasmid transfer AND r-determinants that confer resistance to antibiotics
Viral DNA that integrates into the bacterial chromosome is called a ______
viral DNA that can be integrated in to the host DNA or replicated in the bacterial cytoplasm
to serve as genetic material a molecule must be able to satisfy these 4 criteria:
allow variation by mutation
central dogma of molecular genetics
transcription: three types of RNA are synthesized from DNA