Chapter 1.4 Flashcards
What is the form of sexual reproduction in prokaryotes
- it is binary fission
- > circular chromosome attaches to cell wall
- > eventually the cell membrane/ cell wall grow inward to produce two identical daughter cells
-replication occurs while the cell continues to grow in size
What are episomes
- a subset of plasmids capable of integrating into the genome of the bacterium
- > helps with bacterial diversity
- > allows for bacteria species evolution over time
Name the three recombination processes in bacteria
- transformation
- conjugation
- transduction
What is the process of transformation in the recombination process?
- integration of foreign genetic material into host genome
- > foreign genome comes from other bacteria
- > this bacteria has contents that lyse and spill their contents
What is the process of conjugation in the recombination process?
- it is the bacterial form of mating
- > sexual reproduction
- conjugation bridge forms(bridge is made from sex pili)
- > genetic info transfers across this bridge
- > direction is unidirectional(male to female)
To form a conjugation bridge or pilus, what must the bacteria contain
- to form the pilus
- > bacteria must contain plasmids known as sex factors
- > best studied sex factor is the fertility factor(F cells)
- > during conjugation, the F+ cell replicates this factor and then donates it to the F- cell
-note the sex factor is a plasmid
What is the advantage of conjugation
-it allows for rapid acquisition of antibiotic resistance or virulence factors throughout a colony
How does the term high frequency of recombination relate to conjugation
- it is a full transfer of DNA from the recipient to the donor
- > not just the fertility factor or the F plasmid
What is the process of transduction? What is so special about it
- only genetic recombination process that requires a vector
- >vector is a virus that carries genetic info from one bacteria to another
What are viruses that infect bacteria referred to as? What process of recombination are they involved in
- they are referred to as bacteriophages
- > viruses are obligate intracellular pathogens(cannot reproduce outside of a host cell)
- > therefore, they need the bacteria to reproduce and can change the genome of the host
-this process of recombination is transduction in which the virus affects the genome of the bacteria
What is the process of transposons? Is it only limited to prokaryotes? What happens to a coding region of a gene if a transposon is inserted
- they are genetic elements
- > capable of inserting and removing themselves from the genome
- it is not limited to prokaryotes
- > it is also seen as eukaryotes as well
- if a transposon is inserted into a coding region of a gene
- > then that gene may be disrupted
What are the series of bacterial growth
1) Lag phase
- >bacteria adapts to new local conditions
2) Exponential phase(Log phase)
- >bacteria is adapting
- >growth increases
- >exponential increase in the number of bacteria in the colony
3) Stationary Phase
- >reduction of resources
- >slows reproduction
4) Death phase
- >bacteria have exceeded the ability of the environment to support the bacteria
- >resources in the environment has been depleted
