W3-1: Microbial structure Flashcards
Who invented the first simple microscope?
Antony van Leeuwenhoek and Robert Hooke
Pasteur disproved which theory of microorganism generation?
Spontaneous generation
Koch’s 4 postulates
- pathogen present in all disease cases–absent in healthy
- grow in pure culture
- grown cells must cause disease in healthy animals
- reisolate cells-show they are the same
What is a virulence factor?
Anything that promotes infection
What was Fredrick Griffith’s experiment?
5 categories of infectious agents
- Helmniths (worms)
- Protozoa
- Fungi
- Bacteria
- Viruses
Why are dyp molecules generally positively charged?
so they better bond with the negative interior of cells
Steps in preparing a smear
- Spread culture
- Dry
- Heat fix
- Stain
6 types of bacteria
Gram stain results
(+) purple (crystal violet stain)
(-) redish-pink (crystal violet)
non-gram stainable: colorless
Gram (+) cell wall
Gram (-) cell wall
peptidoglycan (+) vs (-)
larger in gram (+) organisms
Components of peptidoglycan layer
linked peptides
sugars
Bacterial reproduction method
binary fission