Introduction to Bacteria (1) Flashcards
Name bacterial structures A-G
How would you view a bacteria?
Bacteria are visible using light microscopy but to see the ultrastructure of the cell we need to use an electron microscope
Do bacteria have a nucleus?
no
Describe the cytoplasmic membrane
(aka plasma membrane) is a very thin, elastic and semi-permeable membrane around the bacterial cell contents.
Describe the cell wall of a bacteria
cell wall -rigid, giving the cell strength and shape but it is permeable.
Between the plasma membrane and cell wall, which is permeable and semi-permeable?
cell wall - permeable
plasma membrane - semi-permeable
What component do gram-negative bacteria have?
outer-membrane
Is this the cell wall of a Gram-negative or -positive bacteria?
positive
Is this the cell wall of a gram positive or negative bacterium?
negative
What bacteria has a thin cell wall/peptidoglycan?
Gram-negative
Which type of bacteria has a cell wall?
Gram-negative
What is the periplasm?
the space between the inner and outer membrane in Gram-negative bacteria
Name structures A-C and decide if this is a Gram positive or -negative bacterium
Name structures A-D and decide if this is a Gram positive or -negative bacterium
What are the components of the outer membrane of Gram-negative bacteria?
lipopolysaccharides and protein
What colours in light-microscopy identify a Gram-negative/positive bacterium?
+ purple
- red
What bacterium appears red in light microscopy?
Negative
What shape are cocci bacteria?
spherical
What shape are bacilli?
rod-shaped
What bacteria are shown here an dhow do they exist?
white cells (multilobed nuclei showing up red) as well as cocci that are in pairs
Gram- positive
What ways can bacteria exist?
single cells
pairs
chains
clusters
What bacteria are shown here an dhow do they exist?
cocci in longer chains look under the electron microscope
Is bacilli Gram-positive or negative?
negative
Is cocci Gram-positive or negative?
positive
What bacteria does the red stain indicate here?
see rod shaped bacteria that have stained red so these are Gram-negative rods, also known as Gram-negative bacilli
what is shown in the electron microscopic image?
see rod shaped bacteria that have stained red so these are Gram-negative rods, also known as Gram-negative bacilli