Introduction to Bacteria Flashcards
Does bacteria contain a cell wall?
Yes
Do bacteria contain ribosomes?
Yes
Do bacteria contain a nucleus?
No
Explain the DNA in a bacteria cells
Contain single chromosomes that is not enclosed in a nuclear membrane
Why do bacteria have flagellum?
To allow their mobility
Why do bacteria have fimbriae structures?
To allow cell adhesion
What are the two types of bacteria?
Gram positive
Gram negative
What three layers of membrane do gram positive bacteria have?
Plasma membrane
A periplasmic space
Peptidoglycan layer
What 4 layers of membrane do gram negative bacteria contain?
Plasma membrane
Periplasmic space
Peptidoglycan
Lipopolysaccharide layer
How does gram positive appear under the microscope?
Purple
What colour does gram negative appear under the microscope?
Red
In gram staining what is the effect of the addition of acetone on gram negative?
Dissolved the lipopolysaccharide layer
What is the primary stain in gram staining microscopy?
Crystal violet
What shape are cocci bacteria?
Round
What shape are bacilli bacteria?
Rod shaped
What can the lipopolysaccharide layer act as in the body to create a strong immune response?
Antigens
Why do different types of bacteria have different types of flagella?
Because different types of flagella provide different types of motility
What is conjugation?
Ultimately when bacteria cells have sex with one another
What is the purpose of a pillus?
To act like a bridge
To allow the transfer pf plasmids across bacteria
What do some plasmids provide?
Resistance to antibiotics
Do all bacterial contain plasmid?
No
Can the bacteria lose its own chromosome?
No the bacteria can lose its plasmid but cannot lose its own chromosome
How do bacteria cells replicate?
By binary fission
Describe binary fission?
Replication to form identical copies of themselves
What is transformation in bacterial cells?
When living bacterial cells steal left about DNA from dead bacterial cells
What is transduction in bacterial cells?
Process by which foreign DNA is introduced into a cell by a virus or viral vector
What is a bacterioirphage?
It is a virus that infect bacteria
What can bacterioirphages do?
They can eat the bacterium, kill it or inject their DNA into the bacteria to alter its behaviour
What technique is used to amplify DNA?
PCR
Why is enriched agar called enriched agar?
Because it has loads of nutrients in it
How are individual bacteria seen?
With a microscope
How can colonies of bacteria be seen?
With the naked eye
