What provides a mechanism for antibiotic resistance?
What kinds of bacteria prefer what during mating?
Gram negative prefers gram negative
Gram positive prefers gram positive
What is conjugation?
Process by which bacterium transfers genetic material to another through direct contact
What are other names for gram positive and gram negative bacteria?
F+ are gram positive
F- are gram negative
What do gram positive bacteria contain in terms of mating?
F plasmid which allows them to form F pills
What eventually happens when gram positive and gram negative bacteria are mixed together?
They all become gram positive
What is the process of conjugation?
1) F pills of donor cell (gram positive) recognises and binds to proteins on gram negative cell wall
2) Plasmid becomes mobilised for transfer
3) Single strand of plasmid enters the recipient cell
4) Inside recipient cell a complimentary strand is synthesised
What is binary fussion?
The process by which bacteria replicates
What may genetic variation occur due to?
Transfer of DNA
What are spontaneous mutations?
Mutations that occur randomly with no influence from the environment
What does transfer of DNA occur by?
What is transformation?
Genetic alteration due to uptake of extracellular DNA that is advantageous
What is transduction?
Foreign DNA is introduced into a cell by a virus
What is transduction caused by?
What are bacteriophages?
Viruses that infect bacteria
What do bacteriophages contain?
What does the end plate and the tail on a bacteriophage do?
Helps it to attach to bacteria cells
What are the two cycles that bacteriophages enter their DNA into bacteria through?
What is the lytic cycle?
Where the phage overtakes the machinery in the bacteria and starts replicating to form more phages, bacteria cell then bursts and releases them
What is the lysogenic cycle?
DNA from the phage integrates with the hosts chromosome, it can remain dormant or replicate
What can individual bacteria be seen by?
Microscope at 1000x with an oil immersion lens
Staining (such as gram or flourescent)
What can the naked eye see?
Colonies of bacteria
What is culturing used for?
To identify exactly what species of bacteria is present
What do selective mediums allow?
Certains species to grow
What is bacteria naming based on?
The genus and the species
For example for Staphylococcus aureus Staphylococcus is the genus and aureus is the species
What properties do strains of bacteria within the same species have?
What can be used to identify strains?