Exam1 - (4) Bacterial Genetics Flashcards
What are three potential fates of DNA that enter bacteria?
1-Degradation (to be recycled)
2-Integration into a plasmid
3-Integration into the chromosome
Restriction enzymes act on sections of DNA known as
Recognition sequences
What are three methods for introduction of DNA into bacteria?
1-Transformation (DNA absorbed into competent bacteria)
2-Transduction (Phage (Lytic and Lysogenic pathways))
3-Conjugation (transfer of DNA from cell to cell contact)
How is conjugation carried out?
with a sex pillis from an F+ cell to an F- cell (then becomes F+). A single strand of the DNA is broken and then is transferred through pilli in a rolling circle.
Changes to a bacterial genome occur:
constantly
Three ways bacterial genomes can be altered:
1-Mutations
2-Transposible elements
3-Recombination
Of the 100 trillion cells in the human body, what percent are actually human cells?
<10%
What percent of volume do human body bacteria makeup?
<10%
Body bacterial compostions vary by _____ and between _____.
- location on the body
- individuals
Although bacterial composition varies between subjects, ______________ is very similar.
-metabolic potential
About how many species of bacteria have been identified in the oral cavity?
500-1000
What is an oral clone?
a bacterial species identified in the oral cavity by DNA sequencing but never cultured.
About what percentage of oral bacteria have been cultured?
80%
A bacterial cell entering the mouth has two options:
- Expulsion and Death
- Colonization
Within the mouth, different bacteria occupy different environmental _______.
niches (tongue, gingiva, pockets)
