Taxonomy & Genetics (Exam 1) Flashcards
Who is the founder of modern taxonomy?
Carl Linnaeus
What are the 2 parts of the binomial nomenclature?
- genus
- specific epithet
Term for observable characteristics of bacterial cell.
phenotype
Term for total genetic complement of bacterial cell.
genotype
What is the most important genetic method used to produce phylogenetic trees for bacteria?
mass spectrometry
What domain are fungi in? Protists? E. coli?
fungi: eukarya
protist: eukarya
E. coli: bacteria
Which technique is used to identify a bacterium? Which is used to sequence a bacterial genome?
ID: mass spectrometry
sequence: 16S ribosomal RNA analysis
How many genes would be on the E. coli chromosome?
~3000
Two methods by which bacteria acquire new characteristics.
- vertical gene transfer
- horizontal gene transfer
What enzyme makes mistakes which can lead to bacterial mutations?
DNA polymerase
(T/F) All mutations change the coding sequence for proteins in bacteria.
False
3 major methods for genetic transfer between bacteria.
- transformation
- transduction
- conjugation
Match the genetic transfer process to each description:
- DNA transfer by viruses
- naked DNA transfer
- bacterial mating via direct contact
- transduction
- conjugation
- transformation
3 domains of the living world.
- bacteria
- archaea
- eukarya
________ gene transfer is DNA transfer to a non-daughter cell while _______ gene transfer is inheritance of chromosomes by daughter cells.
horizontal
vertical
Transformation requires ________ for incorporation into the bacterial chromosome.
recombination
__________ are viruses which infect bacteria.
bacteriophages
What are the 2 types of transduction cycles that can occur?
- lytic cycle
- lysogenic cycle
The _________ transduction cycle is where viral DNA remains dormant inside bacterial chromosome until it is under stress.
lysogenic cycle
The __________ transduction cycle is when viral DNA is injected and takes over the bacterial host and eventually releases new viruses.
lytic
Bacterial conjugation is important in spreading ______________.
antibiotic resistance
What bacterial structure is required for conjugation to occur?
pilus
Plasmids may encode virulence factors such as _______ and _______.
adhesions
toxins
What causes bacteria to become a pathogen?
virulence plasmids
Function of virulence plasmids.
allow for damage/killing of host cells or attachment for invasion
Specialized transduction is when DNA viral is inserted near ________ in bacteria.
gal gene
When viral DNA is integrated into bacterial chromosome via specialized transduction, what ability does it develop?
ability to metabolize galactose (due to gal gene)
What process differs from specialized transduction in that viral DNA causes bacterial DNA to break down and become packaged into a new bacterium?
general transduction
The difference of general transduction with specialized transduction is due to ____________.
random packaging
What process is a high frequency event which is not accidental, compared to specialized or general transduction?
lysogenic conversion
Regarding lysogenic conversion, viral DNA causes what in a bacterium?
new bacterial phenotype (converted to toxic strain)
_______ plasmid cannot move itself while ________ plasmid can move itself during bacterial mating.
mobilizable
conjugative
DNA segments which mediate movement of DNA within genomes.
mobile genetic elements
What is the significance of mobile genetic elements?
increase antibiotic resistance genes
Term for large chromosomal regions which are only present in pathogenic strains of bacteria.
pathogenicity islands
Pathogenicity islands in bacterial chromosomes are next to ______ encoding genes so that this is present in all bacteria.
tRNA
(T/F) Pathogenicity islands have no essential proteins, only virulence factors or accessory proteins in bacterial DNA.
True
Term for the “jumping genes” where an entire region of genes can move to different plasmids or chromosome sites within a bacterium.
transposons
What can transposons alter in bacteria?
genetic composition (up antibiotic resistance)
(T/F) Transposons and insertion sequences are self-replicating.
False - only move antibiotic resistance genes between replicating molecules
