1
Q
genetics
A
the study of inheritance and inheritable traits as expressed in an organisms genetic material
2
Q
genome
A
the entire genetic complement of an organism
- includes genes and nucleotide sequences
3
Q
DNA
A
- 5’ end terminates in a phosphate group attached to a 5’ carbon
- 3’ end terminates in a hydroxyl group where more can be added in DNA replication
- strands run antiparallel to each other
4
Q
prokaryotic chromosomes
A
- each bacteria cell has a single copy of their genome
- they are haploid cells
- typical chromosome consists of circular DNA localized by the nucleoid
- DNA is folded into loops that are 50-100K base pairs long
- chromosome is the main portion of DNA with associated proteins and RNA
5
Q
plasmids
A
- small molecules of DNA that replicate independently
- non-chromosomal DNA, non-essential genes
- each plasmid carries genes necessary for its replication
- only contain bonus genes
6
Q
what are the bonus genes that can be found on plasmids
A
- fertility factors
- resistance factors
- bacteriocin factors
- virulence factors
7
Q
fertility factors
A
- allows for production of pili
- allows for conjugation
8
Q
resistance factors
A
- cells carry genes for antimicrobial drugs
- cells can transfer resistance factors and create resistance in new cells
9
Q
bacteriocin
A
- carry genes for proteinaceous toxins called bacteriocins
- bacteriocins kill bacteria cells of same/similar species that lack plasmids with this factor
- bacteria cells are killing their competitors
10
Q
virulence factors
A
carry structures, enzymes, or toxins that enable bacterium to become pathogenic
- increased levels = more ill
- help bacteria survive internal body environment
11
Q
DNA replication
A
- theta replication
- bacteria only have one ORI site
- DNA-A binds to ori site to initiate replication
- replication is bidirectional
- each strand of DNA has a leading and a lagging strand
12
Q
DNA-A
A
- enzyme that recognizes and binds to ORI site of a bacteria’s DNA
- when it binds it creates a replication bubble
13
Q
Helicase
A
- helicase enzyme comes in and unwinds the DNA strands from each other
14
Q
single stranded porteins
A
- bind to DNA strands to prevent them from reconnecting after helicase has unwinded them
15
Q
primase
A
- lays down RNA primers in order for replication to occur
- provides the 3’ hydroxyl group for DNA polymerase to begin replication
16
Q
DNA polymerase
A
- only synthesizes 5’ to 3’
- follows behind helicase to synthesize DNA
- can utilize its exonuclease function to take out mismatched pairs and place correct ones from 3’ to 5’; this is the only time it will go in that direction
- this is called proofreading
17
Q
topoisomerase
A
- also called DNA-gyrase
- periodically cuts DNA strand to unwind it and reseals it
- this is to avoid knots in the DNA strand
- what we want antibiotics
18
Q
leading strand
A
- replicates at open 3’ end of DNA template
- replicated from 5’ to 3’
- one RNA primer is needed to replicate
19
Q
lagging strand
A
- replicates at open 5’ end of DNA template
- replicates still only from 5’ to 3’
- multiple RNA primers are needed for replication
- replicates on fragments called okazaki fragments
- replicates away from the replication fork
20
Q
Plasmid DNA replication
A
- large plasmids utilize theta replication
- some small plasmids utilize rolling circle replication
21
Q
Rolling circle replication
A
- utilized by some small plasmids
- allows for conjugation through pili
- can pass on resistance and other plasmid factors to other cells
- ORI site is different from theta replication
22
Q
Rep-A
A
- protein that binds to the ORI site of plasmids that use rolling circle replication
- cleaves one strand of DNA and holds onto its 5’ end
- allows for DNA polymerase to start replication without a primer being needed
23
Q
A
microbiology
flashcards
Decks in class (10)
# Cards
