Intro To Bacteria Flashcards
What are prokaryotes?
Cells with no membrane bound organelles, cell wall, capsule, flagella, pili and fimbrae
What are the two groups of cell walls? What do these contain in their cell walls? How can you tell them apart with a microscope?
Gram positive - peptidoglycons. Retain crystal iodine complex, purple colour.
Gram negative - peptidoglycons, lipopolysaccharides and outer membrane. Do not retain crystal iodine complex, pink colour.
Both gram positive and negative bacteria contain peptidoglycans in their cell wall. What is this made from? How is it linked? What is its purpose?
Sugar derivatives
Peptide bonds
Stabilises bacteria
What are acid fast organisms? How are they protected from WBCs? How fast do they grow? Which inflammatory response are they responsible for?
Bacteria containing large amounts of lipids (called mycolic acids) in their cell wall
Acid protects from acids, alkalis and digestion
Slow growing
In lungs
What are mycoplasma?
Type of acid fast organism
No cell wall - penicillin has no effect
Smallest replicating organisms
What are flagella?
Tail like structures made from flagellum
Chemotaxis, move direction
What are fimbrae and pili? What is their function?
Hair like structures on the surface of bacteria
Sexual reproduction - transfer genes to one another
What are outer membrane proteins?
Proteins on the cell surface which act as pores and binding sites
What is the capsule and slime layer?
Layer of polysaccharides
For specific and non-specific adherence to surfaces
The taxonomy of bacteria is based on genus and species. This is classed due to phenotypes and genotypes. What are phenotypes based on? What are the genotypes based on?
P - Oxygen requirements, growth properties, colonial morphology, biochemical reactions
G - DNA based, whole genome sequence, rNA sequence, variable regions
